• 98% OSS
• 1% free-as-in-beer closed source software
• 1% in-browser tools
• Please don't submit to Reddit, HN, or post this on Twitter. Share, but share with close friends!

Table of Contents

• Tools by Category

• IT News

• Learning Resources

• Notes from the book Software Engineering at Google: Lessons Learned from Programming Over Time

• Josh's Website

• Josh's Tech Blog v2

Tools by Category

• X Asset Management
• X AWS Tools
• X Backups
• X Cloud File Sync and Sharing
• X Collaboration Tools
• X Configuration Management
• X Containers
• X Data Visualization and Dashboards
• X Distributed Systems Tools
• X Editors
• X Git Tools
• X Graphics Stuff
• X High Availability Clustering Tools
• X HPC Tools
• X Kubernetes
• X Live CD Tools
• X Logging
• X Metrics and Time Series Data
• X Monitoring and Alerting
• X Networking Tools
• X Network Performance Analysis Tools
• X Orchestration
• X Package Patch and Repository Tools
• X Performance Analysis Tools
• X Provisioning Tools
• X Python Tools and Resources
• X Python Programming Tutorials
• X RDBMS and SQL Tools
• X RDBMS Performance Analysis Tools
• X Regular Expressions
• X Secrets Management
• X Security Tools
• X Shell Scripting and Tools
• X Software Development Tools
• X SSH Tools
• X SSL Tools
• X Storage Tools
• X Storage Performance Analysis Tools
• X Terminal Tools and SSH Clients
• X Tracing and Profiling
• X Two Factor Authentication
• X Virtualization and SDN
• X VMware Tools
• X VPNs and Tunnels
• X Web and HTTP Tools
• X Web and HTTP Performance Analysis Tools
• X Misc Tools of Note
• X Learning Resources

IT News

A mix of industry and technical, traditional and next generation, dev and ops

• Ars Technica
• CIO.com
• Computerworld
• Dark Reading
• Data Center Knowledge
• DZone
• Engineering Blogs
• eWeek
• High Scalability
• InfoQ
• Infosec Industry
• Light Reading
• Network Computing
• Network World
• Packet Storm
• Re/Code
• SD Times
• TechCrunch
• The New Stack
• The Next Web
• The Next Platform
• The Register
• Webshit Weekly

Asset Management

Asset management, inventories, asset discovery, CMDB, and IPAM - see also Configuration Management

• Collins - Infrastructure source of truth, created by Tumblr -- Scala
• iTop - IT Service Management (ITSM), asset tracking, and ITIL -- PHP
• Fusion Inventory - Multi-lingual, can be paired with GLPI for a killer solution -- perl
• Genesis - Hardware discovery, by Tumblr, can report to Collins -- Ruby
• GestioIP - IP address management (IPAM), web based, supports discovery -- perl
• GLPI - Also provides license management, software auditing, and ticketing -- PHP
• ITDB (IT ITems DataBase) - Includes purchase order management, floor plans, and ISO20000-like features -- PHP
• NetBox - IPAM and DCIM by Digital Ocean -- Python
• Netdisco - Web-based network management and discovery tool, written in perl, uses SNMP -- perl
• NIPAP - Next-generation IPAM -- Python
• OCS-NG (OCS Inventory NG) - Automated inventory, deployment system, can sync with GLPI -- perl
• openDCIM - Data center infrastructure management -- PHP
• Open-AudIT - Track and report assets and configurations, supports Windows too -- PHP
• phpIPAM - IPAM -- PHP
• RackTables - Data center asset management, being updated again! -- PHP
• racktables-contribs - RackTables user-contributed plugins -- PHP
• Ralph - DCIM and CMDB, supports auto-discovery -- Python pip
• Snipe-IT - Uses Bootstrap, web based, supports mobile -- PHP

AWS Tools

And some GCP / Google Cloud

• Action Hero - Uses an AWS SDK feature known as Client Side Monitoring to help you create least privilege IAM Policies for AWS -- Golang
• asecurecloud - A free library of 400+ customizable AWS security configurations and best practices (CF, Terraform, and AWS CLI) -- collection
• awacs (Amazon Web Access Control Subsystem) - Allows for easier creation of AWS Access Policy Language JSON by writing Python code to describe the AWS policies -- Python pip
• Awesome AWS - Curated list of AWS resources -- collection
• aws-shell (formerly Supercharged AWS CLI (SAWS)) - The best CLI for interacting with AWS -- Python pip
• aws-vault - A vault for securely storing and accessing AWS credentials in development environments -- Golang
• AWSConsoleRecorder - Records actions made in the AWS Management Console and outputs the equivalent CLI/SDK commands and CloudFormation/Terraform templates -- Chrome `JavaScript
• AWS Amplify - Front end JS suite that provides a templated foundation for cloud-centric apps including authn, analytics, API, push notifications, Graph QL, and more -- JavaScript
• AWS Copilot - OSS CLI to build, release, and operate apps for ECS and Fargate -- Golang
• AWS Extend Switch Roles - Extend your AWS IAM switching roles by Chrome extension or Firefox add-on -- JavaScript
• AWS IAM Authenticator for Kubernetes - A tool for using AWS IAM credentials to authenticate to a Kubernetes cluster -- Golang
• AWS SAM Local - CLI tool for local development and testing of Lambda applications -- Golang
• AWS Toolkit for Visual Studio Code - Give it a go -- various lang
• boto3 - The AWS SDK for Python 3 -- Python
• boto3_type_annotations - Adds code completion in IDEs such as PyCharm -- Python
• botostubs - boto3 code assistance for any API in any IDE, always up to date -- Python
• Chalice - Microframework for writing and testing serverless apps in Python -- Python
• Chamber - Parameter Store + IAM for secrets including at rest protection, audit trail, and access control policies, by Segment -- Golang
• Chrome AWS SAML Token Expiry Reminder (CASTER) - Automatically re-logs into AWS via ADFS before credentials expire -- Chrome
• CloudBerry Explorer - Windows client for accessing AWS S3 buckets -- closed source Windows
• CloudCraft - Create professional AWS architecture diagrams -- in-browser
• CloudFormation Checklist - A list of all elements you need to have / to test before launching your infra to production -- collection
• CloudFormation Roadmap - Official roadmap -- article
• CloudMapper - Generates network diagrams of Amazon Web Services (AWS) environments and displays them via your browser, by Duo Security -- Python
• CloudSploit Scans - Scan AWS accounts for security risks -- JavaScript
• CloudTracker - Find over-privileged IAM users and roles by comparing CloudTrail logs with current IAM policies. -- Python
• ClusterCloner - Reads the Kubernetes clusters in one location (optionally filtering by labels) and clones them into another (or just outputs JSON as a dry run), to/from AWS, GCP, and Azure -- Golang
• credstash - Secrets management using AWS KMS -- Python pip
• eb_deploy - Elastic Beanstalk blue-green deployment automation -- Ruby gem
• ec2-price-check - Gives a quick price check for an instance type -- shell
• ec2instances.info - Open source and up to date instance price comparison tool -- Python
• ec2.shop - ec2 price checker, supports curl -- various lang
• eksctl - CLI tool for creating and managing clusters on AWS EKS -- Golang
• EKS Distro - Use me for multi-cloud EKS -- various lang
• Fargate - CLI for AWS Fargate, unofficial -- Golang
• Force MFA - Allows users to manage their own passwords and MFA devices but nothing else unless they authenticate with MFA, also makes API calls require MFA -- policy
• Former2 - Generate CloudFormation / Terraform / Troposphere templates from your existing AWS resources via self-hosted web GUI -- JavaScript
• gcpviz - Visualization tool that takes input from Cloud Asset Inventory -- Golang
• haproxy-autoscale - Wrapper for haproxy that handles auto-scaling EC2 instances -- Python
• iamlive - Generate a basic IAM policy from AWS client-side monitoring (CSM) -- Golang
• kappa - CLI tool that makes it easier to deploy, update, and test Lambda functions -- Python
• localstack - A fully functional local AWS cloud stack for offline dev and test -- Python
• Moto - Library that allows your Python tests to easily mock out the boto library -- Python pip
• My Arsenal of AWS Security Tools - List of open source tools for AWS security: defensive, offensive, auditing, DFIR, etc -- collection
• Prowler - For AWS account security assessment and hardenin, based on aws-cli commands -- shell
• refunc - Run AWS Lambda on Kubernetes, a Lambda-compatable API -- Golang
• s3cmd - Backup to AWS via the command line -- Python
• s4cmd - s3cmd with additional features -- Python
• Serverless (formerly JAWS) - Javascript + AWS stack, the entire backend is Lambda functions, server-free -- JavaScript
• Serverless by Design - In-browser or self-hosted GUI for making flow charts for serverless apps -- various lang
• Serverless Stack Toolkit (SST) - extension of AWS CDK that includes a live Lambda dev environment and more -- JavaScript
• Sneaker - Store secrets on S3 using Amazon KMS -- Golang
• ssh2ec2 - SSH into EC2 instances by tag name and/or other metadata filters -- Python pip
• SSM Helpers - Interactive shell with an instance via AWS Systems Manager Session Manager and more -- Golang
• StackMaster - Provides a ton of info pre-CloudFormation run so that you know exactly what will change -- Ruby gem
• StarCluster - Toolkit for using AWS for high performance computing (HPC), by MIT -- Python
• Stout - Easy way to reliably upload a static website to S3, capable of configuring CloudFront and Route 53 -- Golang
• Terraformer - Generate Terraform files from existing infrastructure (reverse Terraform), supports AWS and GCP, by Google -- Golang
• Terraforming - Export all AWS resources into Terraform -- Ruby gem
• Terragrunt Reference Architecture (AWS) - Nice, looking forward to their GCP one -- various lang
• Tools for Amazon Web Services - Amazon's portal for their official tools -- various lang
• troposphere - Python library to create CloudFormation descriptions -- Python pip
• Zappa - Build and deploy serverless, event-driven Python applications -- Python

Backups

Traditional backup software - see also Cloud File Sync and Sharing

• Amanda - The classic -- C perl
• Backupninja - Centralize way to configure and schedule many different backup utilities -- shell
• BURP (BackUp and Restore Program) - Reduces network traffic and the amount of space required by using librsync -- C
• BackupPC - Dedupe and a web GUI for restores -- perl
• Backup - Gem for backup and restore, supports tons of platforms and notifiers (RDBMS, S3, Dropbox, rsync, Hipchat, Zabbix) -- Ruby gem
• Bacula - Open source backup tool, lots of downloads so I guess it's good I don't know -- C
• Back in Time - Similar to TimeMachine, simple GUI backup program -- Python
• Bareos (Backup Archiving REcovery Open Sourced) - Fork of Bacula with additional features -- C
• borgmatic - A simple wrapper script for the Borg backup software that creates and prunes backups-- Python
• bup - Uses the git packfile format, supports global dedupe, can use "par2" redundancy -- Python
• DAR (Disk ARchive) - Better than tar, focuses on disks instead of tapes -- C++
• ddrecover - This should be the first data recovery tool you use -- C
• Deja Dup - GUI for duplicity -- C
• Duplicati - Supports encryption and dedupe -- Mono
• Duplicity - Encrypted bandwidth-efficient backup using the rsync algorithm -- Python
• Elkarbackup - Comes as a ready to use VM, supports Linux and Windows -- PHP
• Fpart - Packs file systems into "partitions" so you can do multi-threaded or multi-node rsyncs -- C
• FSArchiver - Save the contents of a file system to a compressed archive, if one of the checksums doesn't match the file is lost, not the whole backup -- C
• Grsync - GUI for rsync -- Windows OS X C
• Mondo Rescue - Disaster recovery, supports tapes, disks, network and CD/DVD as backup media, multiple filesystems, LVM, software and hardware RAID -- C
• rdiff-backup - Combines the best features of a mirror and an incremental backup in a bandwidth efficient manner -- Windows OS X Python
• Redo Backup and Recovery - Simple bare metal backup and restore, live CD -- Windows
• Relax and Recover (REAR) - BMR, simple, integrates with commercial backup solutions -- shell
• rsnapshot - Uses rsync and hard links, can keep multiple full backups available while using very little disk space -- OS X perl shell
• SafeKeep - Superb project, uses LVM snapshots -- Python
• SnapRAID - Backup program that also stores RAID parity information -- C
• Unison - Multi-OS file sync tool, syncs from both sides, no master -- OS X
• UrBackup - Supports Windows, has a web interface -- Windows C++

Cloud File Sync and Sharing

Sync files to and share from public or private file stores (think Dropbox, Google Drive, etc) - see also Backups

• Drive - Push or pull files to Google Drive via the command line -- Golang
• git-annex Assistant - Sync folder(s) to any device (NAS, mobile, thumb, cloud, etc) via git -- C OS X mobile
• lsyncd - Watches a local directory trees event monitor interface (inotify or fsevents) and kicks off an rsync when things change -- Lua
• Mackup - Sync your Mac application settings to various cloud services or git -- Python OS X
• Nextcloud - Fork of and replacement for OwnCloud, a self-hosted Dropbox -- various lang Windows OS X
• Pydio - Formerly AjaXplorer, AGPL license -- PHP
• rclone - Probably the best cloner, supports almost any source and dest -- Golang
• Seafile - Also offers a paid professional edition with more features, supports most platforms -- C
• SparkleShare - Uses git under the hood, neat -- Windows OS X
• Syncany - Supports tons of different protocols for the transfer (SCP, FTP, Samba, S3, etc) -- Gradle
• Syncthing - Uses an ID rather than an IP address, share your ID with friends and go -- Golang
• Tahoe-LAFS - Free and open decentralized cloud storage system -- Python

Collaboration Tools

ChatOps, code review, groupware, webmail, code sharing, and more - see also Dashboards and Data Visualization and Graphics Stuff and Editors and Git Tools and Software Development Tools

• Citadel - Messaging, collaboration tools, and groupware - an all-in-one package -- C
• Codeshare - In-browser screenshare to teach coding, group code, or as an interview whiteboard -- in-browser
• dev-setup - Automated setup scripts for laptop tools like Sublime Text, AWS, Spark, Android dev, and more -- collection
• Etherpad - Enter, save, and share text/code in a web browser -- JavaScript
• FreeIPA - Identity, policy, and audit suite, think Active Directory for Linux (LDAP, CA, x509, DNS, Kerberos) -- various lang
• FreeMind - OSS mind mapping software, great for brainstorming -- Java Windows OS X
• gcalcli - CLI for Google Calendar -- Python pip
• gmvault - Export/backup and restore your Gmail account -- Python
• Got Your Back - Gmail backups over HTTPS -- Python
• Haste / hastebin - Open source pastebin alternative for sharing code, can be installed locally / on-site -- JavaScript
• Hubot - Chat bot that can do deploys, look up images, integrate with Google Maps, and tons of other stuff -- CoffeeScript
• Isso - A commenting server similar to Disqus -- JavaScript
• Kanboard - Simple Kanban board -- PHP
• Kolab - Unified communication and collaboration system -- PHP
• LDAP Account Manager (LAM) - Full featured LDAP management GUI, can manage almost anything -- PHP
• Mattermost - OSS Slack alternative -- Golang JavaScript
• Mailtrain - Self hosted news letter e-mail app, similar to Mailchimp -- JavaScript
• OpenProject - Web-based project management system built on Ruby on Rails -- Ruby
• osTicket - Routes inquiries created via email, web-forms and phone calls into a web-based customer support platform -- PHP
• OTRS - Open source help desk software -- perl
• OwnTracks - Self-hosted location tracking you can share - use for diaries, work orders, etc -- various lang mobile
• Pandoc - Convert files from one markup format to another, supports a ton of formats -- Haskell
• Phabricator - Suite of web-based software dev collaboration tools, and all-in-one project management tool -- PHP
• PrivateBin - Pastebin where the server has zero knowledge of pasted data, data is encrypted/decrypted in the browser using 256 bits AES -- various lang
• QueryClips - Pastebin for Postgres or my mySQL SQL query sharing -- in-browser
• RainLoop - Simple, modern & fast web-based email client -- PHP
• Redmine - Project management webapp -- Ruby
• Request Tracker - Bug tracking, help desk ticketing, customer service, workflow processes, change management and more -- perl
• Review Board - Code review tool for multiple SCM systems -- Python
• Rocket.Chat - OSS Slack clone built with Meteor.js -- JavaScript
• Roundcube - Browser-based multilingual IMAP client -- PHP
• Scribus - Open source desktop publishing (layout, typesetting, etc), Adobe InDesign alternative -- C++ Windows OS X
• SOGo - Groupware that integrates with Microsoft, Android, and Apple products -- Objective-C OS X
• Sovereign - Set of Ansible playbooks to deploy a suite of self-hosted apps (mail, colab, calendar, file sync, and more) -- Python
• Synergy - Share a single keyboard and mouse with multiple physical computers, only the old version is free now -- closed source Windows OS X
• Taiga - Project management web application with agile/ scrum in mind -- Python CoffeeScript
• TermRecord - Record and playback terminal sessions, outputs self-contained HTML -- Python
• VisioCafe - The largest collection of free Visio stencils -- collection
• WeKan - OSS Trello-like kanban board -- JavaScript
• YOURLS (Your Own URL Shortener) - Lets you run your own URL shortener a'la TinyURL or bit.ly -- PHP
• Zulip - Group chat with chat threads, by Dropbox -- various lang mobile Windows OS X

Configuration Management

OS-level configuration management - see also Asset Management and Orchestration and Package Patch and Repository Tools

• Ansible - CM and orchestration, also can do provisioning -- Python
• Ansible Galaxy - Community site for finding, reusing, and sharing Ansible content -- various lang
• Automatic Server Hardening - Linux hardening cookbooks/manifests/playbooks for Puppet, Chef, and Ansible -- various lang
• awx - Upstream to Ansible Tower - REST API, task engine, etc -- Python
• Blueprint - Reverse engineer a server configuration -- Python pip
• Boxen - Mac / OS X configuration management -- Ruby gem OS X
• Jenkins Ansible Tower Plugin - Run Ansible Tower jobs as a build step -- Java
• Oxidized - RANCID replacement, supports many platforms (Cisco, Brocade, Juniper, Citrix, etc) -- Ruby gem
• RANCID - (Really Awesome New Cisco confIg Differ) - Pulls and saves network device configs and saves them into a CVS, now supports git -- C
• Reclass - External node classifier for most CM systems, allows for a tagging system that's a layer above the CM tool -- Python
• Salt / Saltstack - Orchestration, server provisioning, and configuration management -- Python

Containers

Linux containers, container orchestration, networking, Docker, OpenShift, and related tools - see also Distributed Systems Tools and Virtualization and SDN and Web and HTTP Tools

• Alpine Linux - Super minimal BusyBox based Linux distro, perfect for hosting containers -- various lang
• Anchore - A centralized service for inspection, analysis and certification of container images -- Golang
• appscale - Open source implementation of Google App Engine -- Python
• Awesome Docker - Massive Docker collection -- collection
• Buildah - A low-level interface to core-utils, build container images with the scripting language of your choice without using Dockerfiles, compare to Podman -- Golang
• cadvisor - Analyzes resource usage and performance characteristics of running containers -- Golang
• cert-manager - Automate the management and issuance of TLS certificates from various issuing sources -- Golang
• Cilium - Transparently secure layer 7 services, communicate based on identity groups, load balancing, BPF-level for performance and instrumentation & more -- Golang
• Clear Linux - New name for Clear Containers, attempts combine the security advantages of VMs with the deployment advantages of containers -- various lang
• Cloud Foundry - Open source PaaS by VMware and Pivotal -- Golang Ruby
• ClusterCloner - Reads the Kubernetes clusters in one location (optionally filtering by labels) and clones them into another (or just outputs JSON as a dry run), to/from AWS, GCP, and Azure -- Golang
• CodeReady Containers - Run OpenShift 4.x locally on your laptop, RECOMMENDED -- various lang
• CodeReady Single Node Cluster (SNC) - Script to create an OpenShift 4.x single node cluster on Linux using KVM -- shell
• crane - Docker orchestration, similar to Docker Compose -- Golang
• ctop - ncurses top-like UI for containers -- Golang
• Dex - A federated OpenID Connect provider -- Golang
• distroless - "Distroless" images contain only your application and its runtime dependencies and nothing else, by Google -- various lang
• docker-debug - Attach a new "debug container" to existing namespaces so you don't have to include debug tools in the app containers -- Golang
• docker-gc - Docker garbage collection of containers and images -- shell
• DockerSlim - Uses static and dynamic analysis to create skinny image variants of your fat images -- Golang
• dockerviz - Great tool for analyzing images -- Golang
• Docker Bench - Checks for dozens of common best-practices around deploying Docker containers in production -- shell
• Docker Compose - Define and run multi-container apps with Docker, previously known as fig, official -- Python
• Docker Desktop - Notable because it works without admin / root, Mac and Windows -- Golang
• Docker Distribution - AKA Docker Registry 2.0 - pack, ship, store, and deliver containers -- Golang
• Docker Hub - Official Docker images for many projects -- various lang
• Docker Toolbox - Docker Client, Machine, Compose, Kitematic, VirtualBox, and the boot2docker VM in a single package, official -- various lang
• dockerfile-security - Open Policy Agent (OPA) rules for dockerfiles that can be integrated into your pipeline -- collection
• Dockit - Jump into a container image of your choosing, taking all the files from the current directory with you -- shell
• Dokku - Docker powered mini-Heroku (PaaS) in around 100 lines of bash -- shell
• dumb-init - Minimal init system for containers, by Yelp -- C
• Fedora CoreOS - The best of CoreOS + Fedora Atomic Host, upstream to RHEL CoreOS, successor to now sunset RHEL / Fedora Atomic & Container Linux -- various lang
• Flatcar Container Linux - Immutable Linux distribution for containers, the modern choice -- various lang
• gvisor - User-space kernel, can be used to sandbox containers, by Google -- Golang
• img - Standalone, daemon-less, unprivileged Dockerfile and OCI compatible container image builder -- Golang
• Jenkins Docker Slaves Plugin - Aka Dockins, execute a Jenkins job inside one or more containers, supports most job types -- Java
• jib - Build container images for your Java applications, by Google -- Java
• Kata Containers - A mix of Clear Containers / Clear Linux and Hyper's runV -- frankencontainers various lang
• Kitematic - GUI Docker management on Mac & Windows (laptops), official -- JavaScript Windows OS X
• Kraken P2P Docker registry capable of distributing TBs of data in seconds using a slightly modified BitTorrent protocol -- Golang
• LinuxKit - Toolkit for building custom minimal, immutable Linux distributions -- Golang
• Logspout - Log router for Docker containers -- Golang
• Minishift - OpenShift in a VM for testing / learning -- Golang
• ngnix-proxy - Nginx proxy for Docker containers using docker-gen, recommened -- Python
• Nomad - Highly scalable application, process, and container orchestraction, multi-cloud support -- Golang
• OKD - The upstream for Red Hat's OpenShift 3.x, previously OpenShift Origin -- Golang
• OKD Install - Set of file that installs OKD 3.x (OpenShift's upstream, formerly OpenShift Origin) on a single CentOS VM for testing & dev -- shell
• OpenShift Container Platform Install Demo - Install an OpenShift 4.x demo system on Linux, Windows, or Mac, by Red Hat -- various lang
• Panamax - Containerized app creator with an open-source app marketplace hosted in GitHub -- various lang
• Permission Manager - Excellent solution for standalone or onprem isolated clusters -- Golang
• pipework - SDN for Linux Containers -- various lang
• Popeye - Scans the live cluster for dead or unused resources such as ports mismatches, metrics utilization, probes, container images, RBAC rules, naked resources, etc -- Golang
• Portainer - Web interface for Docker aka us-for-docker -- JavaScript
• pulumi - HOT create and deploy cloud programs that use containers, serverless functions, hosted services, and infrastructure, on any cloud, supports most languages -- various lang
• Pulumi Cloud Framework - Multi-cloud support via a single API -- various lang
• Rancher - Provides a complete platform for operating Docker in production -- various lang
• Registrator - Service registry bridge for Docker, supports Consul, etcd -- Golang
• swarm-viz - Docker Swarm visualizer -- JavaScript
• Watchtower - Monitors your running Docker containers and restart them when a new image is available -- Golang
• Weave - Virtual network that connects Docker containers deployed across multiple hosts -- Golang

Dashboards and Data Visualization

Dashboards for monitoring, alerting, metrics, data visualization tools, and status boards - see also Metrics and Time Series Data and Logging and Monitoring and Alerting

• Bigdesk - Live charts and statistics for Elasticsearch cluster -- JavaScript
• Cachet - Create beautiful, responsive status pages -- PHP
• Cacti - Web-based network monitoring and graphing tool designed as a front-end to RRDtool -- PHP
• Facette - Time series data visualization and graphing software -- Golang
• Flame Graphs - Stack trace visualizer by Brendan Gregg -- perl
• Gource - Software version control visualization tool -- C++
• Graphene - Graphite dashboard in D3 and Backbone -- JavaScript
• Hygieia - Visualize near real-time status of the entire delivery pipeline, by Capital One -- Java
• Kibana - Warning, no longer free software see this page -- beware
• ksar - Creates pretty graphs from sar output -- Java
• logstalgia - Web site access log visualization tool, aka Apache Pong -- C++
• Loki - Like Prometheus but for logs -- Golang
• lsofgraph - lsof output into to Graphviz -- Lua
• Grafana - Modern dashboard for Graphite -- JavaScript
• grafana-statusmap - Grafana status panel -- JavaScript
• Mozaik - Create beautiful dashboards using Node/React/D3 -- JavaScript
• MRTG (Multi Router Traffic Grapher) - Still being updated -- perl
• Nagdash - Dashboard / NOC screen for Nagios -- PHP
• NagVis - Visualization suite for Nagios -- PHP
• Nagiosgraph - Another visualization tool for Nagios data -- perl
• Network Weathermap - Network visualization tool, create a "weather map" just like big ISPs use, not dead yet -- PHP
• pdash - web dashboard for linux using data mainly served by psutil -- Python pip
• PNP4Nagios - Analyzes performance data provided by plugins and stores them automatically into RRD-databases -- PHP
• promviz - Visualize the traffic of your clusters in realtime from Prometheus data -- Golang
• redash - Web application that allows to easily query an existing database, share the dataset and visualize it in different ways -- various lang
• Seyren - Alerting dashboard for Graphite -- Java
• Smashing - Successor to Dashing -- Ruby
• Staytus - Complete solution for publishing the latest info about issues with your web applications, networks or services -- Ruby
• Tessera - Graphite dashboard in Python -- Python pip
• Thruk - Web interface for Nagios, Icinga, Shinken and Naemon, can create SLA reports, has a mobile client -- JavaScript
• vnstati - Creates PNG images using vnStat data -- built-in

Distributed Systems Tools

DCOSes, microservices, service discovery, schedulers, and related tools for dynamic, warehouse-scale computing - see also Containers and HPC Tools

• Akkio - Data placement service that determines how and when to move information in order to optimize retrieval speed for people across the globe, using the minimum required number of copies -- various lang
• Avro - Data serialization system with backwards compatible schemas -- Java
• Chaperone - End-to-end Kafka auditing (data loss, latency, message duplication, etc), by Uber -- Java
• confd - Manage local application configuration files using templates and data from etcd or consul -- Golang
• Crossplane - Multicloud control plane -- Golang
• Cruise Control - Fully automate the dynamic workload rebalance and self-healing of a Kafka cluster, by Linkedin -- Java
• Cruise Control UI - Also by Linkedin -- JavaScript
• consul - Service discovery and configuration via DNS or HTTP, great for auto-scaling -- Golang
• consul Tools - Official, includes consul-template and others -- various lang
• DoctorKafka - Kafka cluster auto healing and workload auto-balancing -- Java
• etcd - Distributed, consistent key-value store for shared configuration and service discovery -- Golang
• fabio - Zero-conf load balancing HTTP(S) router for deploying microservices managed by Consul, by eBay -- Golang
• Flink - Next-generation true stream processing platform for real-time analytics -- Java
• GraphQL - Alternative to REST, allows clients to define the structure of the data, subscribing to data flows, and more -- various lang
• Hystrix - Circuit breaker library to stop cascading failures, by Netflix -- Java
• Ignite - General-purpose in-memory platform for in-memory computing use cases -- Java
• jespen - A framework for distributed systems verification, with fault injection -- Clojure
• JVM Profiler - Distributed profiler to collect JVM performance and resource usage metrics and serve them for further analysis, by Uber -- Java
• Kafka - Stream processing platform (logs, IoT metrics, anything) -- Java
• kafkacat - Generic CLI producer and consumer -- C
• Kong - Microservice abstraction layer (aka API Gateway or Service Mesh), great for creating API endpoints -- Lua
• LogDevice - A distributed data store for logs, by Facebook -- C++
• Mantl - Complete microservices infrastructure built using OSS tools by Cisco -- various lang yowza
• MaxScale - General purpose DB query proxy, router, and load balancer, by MariaDB -- C
• mcrouter - memcached protocol router for scaling memcached, by Facebook -- C++
• Mitogen - Python library for writing distributed self-replicating programs like magic -- Python
• nsq - Realtime distributed messaging platform / message queue -- Golang
• OpenStack - Private cloud -- Python
• Pinpoint - Application Performance Monitoring (APM) for distributed systems, based on Dapper -- Java
• Plumber - Read and write messages to Kafka, RabbitMQ, Google Cloud PubSub, and more -- Golang
• redis-cell - Redis module that provides rate limiting in Redis as a single command using GCRA -- C
• Redisson - Distributed and scalable Java data structures on top of Redis -- Java
• Redpanda - Kafka compatible event streaming platform no Zookeeper, no JVM, and no code changes required -- C++
• Riemann - Aggregates events from your servers and applications with a powerful stream processing language, for distributed systems, similar to Borgmon -- Clojure
• Serf - Decentralized solution for service discovery and orchestration -- Golang
• Spark - Near real-time analytics processing platform, succeeded by Flink (real streaming vs Spark's microbatches) -- various lang
• Spring Cloud Config - Allows Java Spring to read config info from service discovery or similar source -- Java
• uReplicator - Improved Kafka MirrorMaker by Uber -- Java
• Zookeeper - Distributed configuration service, synchronization service, and naming registry -- Java

Editors

IDEs, text & source editors, vim plugins, and similar tools - see also Graphics Stuff and Collaboration Tools

• 010 Editor - Professional hex editor that supports binary templates for easy reading, scripting, and more -- closed source
• activate-power-mode - Activate POWER MODE and write code in style, an Atom plugin -- CoffeeScript
• Atom - Superb text editor, created by GitHub -- CoffeeScript
• Atom Vim Mode - vi/vim style controls for Atom -- CoffeeScript
• Atom Linters - A collection of lint tools for the Atom editor -- various lang
• Brackets - Modern editor that understands and focuses on web design, by Adobe -- JavaScript
• LargeFile - vim plugin that automatically disables certain things so you can edit large (multi-gig) files faster -- vim
• Light Table - Next-generation editor that gives you instant feedback -- Clojure
• MacDown - Markdown editor and live preview for Mac -- Objective-C OS X
• MacVim - Has far more features than the vim that's included with the OS -- C
• Nuclide - Collection of packages for Atom to provide IDE-like functionality for a variety of programming languages and technologies, by Facebook -- JavaScript
• Notepad++ - Killer GPL'ed text editor for Windows -- C++
• percol - Interactive grep (search) tool -- Python
• Powerline - Provides various statues on the bottom of your session, flexible -- Python
• Textmate - GUI text editor for OS X -- C++
• UltiSnips - The ultimate snippet solution for vim -- Python
• vim-json - A better JSON plugin for vim -- vim
• vim-snippets - snipMate & UltiSnip snippets -- vim
• Vimium - Chrome extension that provides vi/vim style shortcuts for navigation and control -- CoffeeScript Chrome
• Visual Studio Code - Open Source - Open source version of Microsoft's product -- JavaScript
• Vundle - Popular plug-in manager for vim -- vim
• wasavi - vim/vi controls in browser text areas -- JavaScript Firefox Chrome
• wxHexEditor - Free hex editor, disk editor, and big file editor for Linux, Windows and Mac OS X -- C
• YouCompleteMe - Fuzzy-search code completion engine for vim -- Python

Git Tools

Tools for interacting with git and GitHub - see also Software Development Tools

• BFG Repo-Cleaner - Scrub large blobs and sensitive data from git history -- Scala
• blackbox - Safely store secrets in Git, by Stack Exchange -- shell
• Completion - Shell tab completion for git branch names -- shell
• Gerrit - Web based code review and repo management for Git -- Java
• git-fat - Like git-media but without the Ruby dependencies -- Python
• GitKraken - Probably the best multi-platform git GUI -- closed source Windows OS X Linux
• GitHub Pull Request Builder Plugin (gprbp) - Jenkins plugin that allows certain comment strings to kick off builds or take other actions -- Java
• GitLab - Kinda like an open source GitHub, has both a community and paid version -- Ruby
• GitLab CI - CI that integrates with GitLab -- Ruby
• gitsome - Supercharged CLI with GitHub integration -- Python
• GitUp - Maybe the best git GUI -- Objective-C
• gitwatch - Automatically commit changes when specified files or directories are modified -- shell
• Git Interfaces, Frontends, and Tools - Massive list on the official kernel.org wiki -- various lang
• Gogs - Painless, self-hosted Git service written in -- Golang
• hub - Official CLI for GitHub -- Golang
• myrepos - Flexible tool for managing many repos -- perl
• Signing - Sign commits and/or tags using GPG keys to verify the identity of the commiter -- built-in

Graphics Stuff

Not everything happens in the browser or on the command line - see also Collaboration Tools and Data Visualization and Dashboards

• Avidemux - Simple, all-in-one, GUI video editor and converter -- C++ Windows OS X
• Blender - 3D graphics software for animated films, visual effects, art, 3D printed models, and more -- C Python Windows OS X
• blockdiag - Generate simple block/sequence/activity/network diagrams from text files -- Python pip
• Darktable - Photography workflow application and RAW developer, Adobe Lightroom replacement -- C OS X
• draw.io - Free online flow chart maker / Visio alternative, can be self-hosted -- in-browser
• GlyphSearch - Search for icons from Font Awesome, Glyphicons, IcoMoon, Ionicons, and Octicons -- collection
• GIMP (GNU Image Manipulation Program) - Open source Adobe Photoshop replacement -- C
• Graphviz - Graph visualization and flow chart software -- wacky license
• Greenshot - The best Windows screenshot tool -- C# Windows
• Inkscape - Open source vector image editor, Adobe Illustrator replacement -- C C++ Windows Mac
• LICEcap - Capture an area of your desktop and save it to a GIF -- C Windows OS X
• mac2imgur - Auto-upload screenshots to Imgur -- Swift OS X
• maim - The most powerful and flexible Linux desktop screenshot tool -- various lang
• Media Player Classic - Home Cinema (MPC-HC) - Open source media player for Windows -- C++ Windows
• OpenShot - Video editing software, 2.0 will support other additional platforms -- Python Windows OS X
• Origami - Interactive UI design prototyping without programming, by Facebook -- various lang
• Pencil - Open source GUI prototyping and mockup tool, supports all platforms -- Windows OS X
• PlantUML - Easily create beautiful UML Diagrams from simple textual description -- Java
• ScreenToGif - Record a selected area of your screen, edit and save it as a GIF or video -- C++
• ShareX - One of the best screenshot/screencast capture and sharing tools for -- Windows OS X
• Skitch - Feature-rich screenshot editing, sharing, and annotation tool Mac/OS X -- closed source
• VLC Media Player - Media (music, video, etc) player and streaming server -- C Windows OS X
• yEd Graph Editor - Flowcharts and UML diagrams -- closed source

High Availability Clustering Tools

HA clustering tools including storage replication, failover, VIPs, and more - see also Distributed Systems Tools and Containers

• Corosync - HA framework and cluster engine -- C
• csync2 - General purpose cluster file sync tool -- C
• DRBD (Distributed Replicated Block Device) - Mirror block devices to a remote system aka replication -- C
• Ganeti - Wrappers around existing tools to make it easy to create HA clusters, by Google -- Python
• HAproxy - Open source software load balancer -- C
• haproxyctl - Wrapper to talk to the HAProxy socket, as well as regular init (start stop restart) shit -- Ruby
• keepalived - Load balancing and high availability -- C
• huptime - Zero downtime restarts of unmodified programs -- C
• Linux-HA - Building blocks for high availability systems -- wiki-and-collection
• LVS (Linux Virtual Server) - Linux-based load balancer, also includes the IPVS kernel module -- C
• Multibinder - Simple Ruby daemon that makes true zero downtime reloads simple, by Github -- Ruby
• Pacemaker - HA resource manager -- C
• rcron - cron redundancy and failover, ensures a job will only run on the "active" machine -- lost-to-the-internet C
• rmanager - Resource group manager daemon for cluster services -- built-in
• Seesaw - Load balancer based on Linux Virtual Server (LVS), by Google -- Golang
• Traefik - Modern HTTP reverse proxy and load balancer, supports many backends -- Golang
• UCARP - VIP management using the CARP protocol -- C

HPC Tools

High performance computing for simulations, supercomputing, shared memory systems, and grid computing - see also Distributed Systems Tools and Containers

• Clustered File System - Ceph, GlusterFS, Lustre, etc, take your pick -- various lang
• HTCondor - Workload management system for compute-intensive jobs, formerly Condor
• Maul Cluster Scheduler - Precursor to the Moab HPC Suite
• MPI for Python (mpi4py) - Python bindings for the Message Passing Interface (MPI) standard
• MPICH - High-performance and widely portable implementation of the Message Passing Interface (MPI) standard
• MUNGE - Authentication service for creating and validating credentials, designed for HPC
• MVAPICH2 - MPI-3 over OpenFabrics-IB, OpenFabrics-iWARP, PSM, and TCP/IP
• OpenMP - API that supports multi-platform shared memory multiprocessing programming in C, C++, and Fortran -- article
• OpenMPI - Popular Message Passing Interface (MPI) library -- C
• Open Grid Scheduler - Formerly known as Sun Grid Engine -- C
• OSCAR (Open Source Cluster Application Resources) - Makes it easy to create a Beauwulf-type HPC cluster
• Rocks Cluster Distribution - Linux cluster distribution that enables end users to easily build computational clusters, grid endpoints and visualization displays
• Slurm (Simple Linux Utility for Resource Management) - One of the mostly widely used schedulers
• StarCluster - Toolkit for using AWS for HPC, by MIT -- Python
• TORQUE (Terascale Open-source Resource and QUEue Manager) - An updated and extended version of Portable Batch System (PBS)

Kubernetes

Kubernetes is ancient Egyptian for "he who has won the platform wars", see Learning Resources for tutorials

• Nomad - Consdier Nomad as a lightweight alternative to Kubernetes, by Hashicorp -- Golang
• Ambassador - Kubernetes-native API gateway built on Envoy proxy includes gRPC, auth, TLS, and more -- Python
• Argo - Container-native workflow engine implemented as a Kubernetes CRD (Custom Resource Definition) -- Golang
• Awesome Kubernetes - Collection -- collection
• Banzai Cloud - Kubernetes based, open source, multi-cloud with all the good stuff baked in (Prometheus, CICD pipelines, and more) CHECK THIS -- various lang
• ClusterCloner - Reads the Kubernetes clusters in one location (optionally filtering by labels) and clones them into another (or just outputs JSON as a dry run), to/from AWS, GCP, and Azure -- Golang
• Contour - Kubernetes ingress controller using Lyft's Envoy proxy -- Golang
• DevSpace - Build, test and run code directly inside any Kubernetes cluster, no more waiting for rebuild + redeploy, run code instantly -- Golang
• draft - Streamlined Kubernetes development with sandbox testing & deployment in seconds -- Golang
• draino - Automatically drains Kubernetes nodes based on labels and node conditions, can be used for auto-remediation -- Golang
• drone - CI platform built on Docker / containers, can also deploy to Kubernetes -- Golang
• Eirini - Kubernetes backend for Cloud Foundry -- Golang
• Envoy Proxy - Sidecar container for distributed applications or microservices, data plane service mesh / edge proxy -- C++
• Escalator - Batch or job optimized horizontal autoscaler for Kubernetes -- Golang
• Fluent Bit Kubernetes Daemonset - The best logger, super light weight -- Golang
• Flux - Tool that automatically ensures that the state of a Kubernetes cluster matches the config in git via Kubernetes operators -- Golang
• Flannel - Network fabric for containers via etcd, designed for Kubernetes -- Golang
• Gangway - Enable authentication flows via OIDC (OpenID Connect Tokens) for a Kubernetes cluster -- Golang
• Gitkube - Build and deploy docker images to Kubernetes using git push -- various lang
• Gloo - Gateway / abstraction layer between upstream services, based off of Envoy -- Golang
• gravity - Creates snapshots of a Kubernetes cluster that can be restored elsewhere (on-prem, DR situation, etc) -- Golang
• Helm - tool for managing Kubernetes charts (packages of pre-configured Kubernetes resources) -- Golang
• Heptio Sonobuoy - Kubernetes end to end conformance testing and debugging tool -- Golang
• Istio - Envoy + auth, policy enforcement, telemetry, traffic flow management etc control plane that runs on top of Mesos and Kubernetes, service mesh control plane -- various lang
• Istio Operator - An operator that manages Istio deployments on Kubernetes, by Banzai Cloud -- Golang
• Jenkins Kubernetes Plugin - Use a Kubernetes cluster to dynamically provision a Jenkins agent (using Kubernetes scheduling mechanisms to optimize the loads), run a single build, then tear-down that agent -- Java
• Jenkins X - Another Kubernetes deployer -- various lang
• k3s - Lighweight Kubernetes in a 40mb binary, built for the edge or laptop or Pi, by Rancher -- Golang
• k8s-prom-hpa - A Kubernetes horizontal pod autoscaler with Prometheus custom metrics -- Golang
• Keel - Stateless, automated Kubernetes deployment updates -- Golang
• Kind - Run local Kubernetes clusters using Docker container “nodes", great for local development -- Golang
• kops - CLI for managing, upgrading, maintaining, creating, etc Kubernetes clusters -- Golang
• kubepug - Kubernetes PreUpGrade (Checker) -- Golang
• kube-applier - service that enables continuous deployment of Kubernetes objects by applying declarative configuration files from a Git repository to a Kubernetes cluster -- Golang
• kube-bench - Compliance checker for Kubernetes CIS benchmarks -- Golang
• kube-hunter - Hunt for security weaknesses in Kubernetes clusters -- Python
• kube-prometheus - Use Prometheus to monitor Kubernetes and applications running on Kubernetes -- Golang
• kube2iam - Provide IAM credentials to containers running inside a kubernetes cluster based on annotations -- Golang
• kube2pulumi - k8s yaml in, language of your choice out -- Python
• Kubecost - Creates cost future and past models so you can see and predict your spend -- Golang
• kubectl-debug - Debug your pod via a new container with every troubleshooting tools pre-installed -- Golang
• kubectx - Easily switch between kubectl contexts and namespaces, also includes the kubens tool -- Ruby
• kubed - Perform periodic cluster snapshots, provide temp storage for deleted objects, automatic event forwarding, deliver notifications via various channels for Kubernetes -- Golang
• KubeEdge - CNCF project to run Kubernetes at edge -- Golang
• KubeLinter - Supports k8s and Helm -- Golang
• Kubernetes - Open source orchestration system for Docker containers, by Google -- Golang
• kubernetes-cloudflare-sync - Run in your Kubernetes Cluster on GKE and sync DNS records on Cloudflare with your nodes IPs to avoid GCP LB fees -- Golang
• kubernetes-deploy - tool that helps you ship changes to a Kubernetes namespace and understand the result, by Shopify -- Ruby
• kubernetes-event-exporter - Exports missed events, there are tons you don't know about -- Golang
• Kubernetes IN Docker (KinD) - Tool for running local Kubernetes clusters using Docker container "nodes" -- Golang
• Kubernetes Job/CronJob Notifier - Puts a message into Slack -- Golang
• Kubernetes Network Policy Recipes - Example recipes for Kubernetes Network Policies that you can just copy paste -- collection
• kubespray - Deploy a production ready Kubernetes cluster, a Kubernetes Incubator project -- Golang
• kubewatch - Kubernetes event watcher and handler (currently only publishes to Slack channels, integrations wanted!) -- Golang
• Kube Forwarder - GUI Kubernetes port forwarding manager -- JavaScript
• kustomize - The preferred templating tool, now built-in to kubectl, official -- Golang
• linkerd2 - The project formerly known as Conduit has been merged into this -- Golang
• Lokomotive - Kubernetes distribution with baked in multi-cloud and Terraform support, by Kinvolk -- various lang
• MetalKube - Bare metal provisioning for Kubernetes, by Red Hat -- Golang
• MetalLB - Load balancer for bare metal Kubernetes clusters, by Google -- Golang
• Microk8s - Alternative to minikube, by Canonical -- shell
• minikube - Kubernetes environments on your laptop -- Golang
• missing-container-metrics - Exports container exit code, OOM kill status and number of restarts to Prometheus -- Golang
• MKIT (Managed Kubernetes Inspection Tool) - A quick way to assess several common misconfigurations in their Kubernetes environment (AKS, EKS, GKE) -- Dockerfile
• Octant - Web based representation of a Kubernetes cluster, by VMware -- various lang
• Prometheus Operator - Creates/configures/manages Prometheus clusters atop Kubernetes -- Golang
• Reloader - Reloader can watch changes in ConfigMap and Secret and do rolling upgrades on Pods -- Golang
• Rook - Self managing, self healing storage orchestrator for Kubernetes via an operator plugin, see also EdgeFS -- Golang
• shell-operator - Integration layer between Kubernetes cluster events and shell scripts by treating scripts as hooks triggered by events -- Golang
• skaffold - Easy and repeatable Kubernetes development, test locally then push to a cluster, by Google -- Golang
• Sloop - Monitors Kubernetes, recording histories of events and resource state changes and providing visualizations to aid in debugging past events, by Salesforce -- Golang
• Squash - Debug applications from your terminal or IDE while they run in Kubernetes or OpenShift (locally or remotely) -- Golang
• SuperGloo - Service mesh management and orchtestration -- Golang
• Telepresense - Local development against a remote Kubernetes or OpenShift cluster -- Python
• Teleport - Auditing bastion host & middleman, now supports the Kubernetes apifserver protocol -- Golang
• Typhoon - Minimal and free Kubernetes distro, great for testing and learning on small systems -- various lang
• Wormhole - CNI plugin for Kubernetes that uses WireGuard for creating a full mesh encrypted network between each host in the Kubernetes cluster. The Kubernetes API is used to coordinate key exchange and configuration -- Golang
• Vault Secrets Operator - Kubernetes operator for Hashicorp Vault -- Golang
• Velero - Manage disaster recovery for your Kubernetes persistent volumes and cluster resources, formerly Heptio Ark -- Golang
• version-checker - Check image versions running in the cluster vs the newest and then alert via Prometheus when newer ones are available for evaluation -- Golang
• virtual-kublet - kublet implementation that masquerades as a kubelet for the purposes of connecting Kubernetes to other APIs (Fargate, ACI, IoT, Nomad, Azure, etc) -- Golang
• Voyager - HAProxy backed secure L7 and L4 ingress controller for Kubernetes -- Golang

Live CD Tools

Security, recovery, bootable USB/CD/DVD creation tools, diagnostics, and more - see also Security Tools and Backups and Provisioning Tools

• BlackArch Linux - Penetration testing Linux distro, based off of Arch Linux -- various lang
• CAINE (Computer Aided INvestigative Environment) - Computer forensics on a live CD -- various lang
• DBAN (Darik's Boot and Nuke) - Spinning disk wiper -- various lang
• Easy2Boot - Create multiple bootable Linux ISOs on the same USB drive -- Windows
• GParted Live - Small, bootable ISO that contains gparted - great for resizing a non-LVM root file system -- C
• Hiren's Boot CD - Re-adding, updated after 6 long years -- closed source
• Kali Linux - Penetration testing Linux distro -- various lang
• Network Security Toolkit (NST) - Live CD that includes most tools in insecure.org's top 125 tools list -- various lang
• NirLauncher - USB live distro that contains all of the NirSoft utilities and more, essential for Windows -- closed source Windows
• PALADIN - Easy to use Linux-based live CD for forensic analysis -- various lang
• Rufus - Create bootable USB flash drives -- Windows
• Security Onion - Linux distro for IDS, NSM, and log management -- various lang
• Stresslinux - Hardware burn-in and stress testing -- various lang
• System Rescue CD - System recovery CD that focuses on Linux system recovery -- various lang
• Tails - Aims at preserving your privacy and anonymity via Tor -- various lang
• Ultimate Boot CD (UBCD) - Tons of x86 diagnostic and stress test tools on a single CD -- closed source Windows
• UNetbootin - Create custom, bootable USB Linux CDs -- Windows OS X
• YUMI - Multiboot USB creator, Linux and -- Windows

Logging

Log management, analysis, analytics, and collection from any source - see also Data Visualization and Dashboards and Metrics and Time Series Data and Monitoring and Alerting

• Adiscon LogAnalyzer - Slick web interface for syslog messages -- PHP
• Countly - Mobile and web analytics and marketing platform -- JavaScript
• Elastalert - Send alerts based on ElasticSearch logs (http 500 increase/spike, any custom string, etc) -- Python
• ElasticDump - Import / export tools for Elasticsearch -- JavaScript
• ElasticHQ - Does not yet support ES 5.x -- JavaScript
• Elasticsearch - Warning, no longer free software see this page -- beware
• Elasticsearch Exporter - Script to import/export data from ElasticSearch to various other storage systems -- JavaScript
• Errbit - Self-hosted error catcher, Airbrake API compliant -- Ruby
• Filebeat - By Elastic, the next generation Logstash Forwarder -- Golang
• fluentbit - Fast and lightweight log processor, part of the fluentd family -- C
• Fluentd - Unified logging layer, often used with Kubernetes / OpenShift / containers -- Ruby gem
• Flume - Distributed, reliable, and available service for efficiently collecting, aggregating, and moving large amounts of log data -- Java
• GoAccess - Real-time web log analyzer and interactive viewer that runs in a terminal and/or dashboard -- Windows OS X
• Graylog2 - Log capture and analysis -- various lang
• lnav - Advanced log file viewer for the small-scale, terminal/ncurses based -- C++
• Log Courier - Enhanced fork of Logstash Forwarder -- Ruby
• Logagent - Lightweight log shipper, like Filebeat and Logstash in one without the JVM footprint -- JavaScript
• Logplex - Distributed syslog log router, uses Redis, by Heroku -- Erlang
• logstash - Collect, parse, and store logs. A component of the popular ELK stack -- Ruby
• Logster - Utility for reading log files and generating metrics to configurable outputs by Etsy -- Python
• Logwatch - Monitor logs and send an e-mail when event(s) occur -- perl
• Mamomo - Web analytics platform with a killer UI, formerly PIWIK -- PHP
• multilog - Reads a sequence of lines from stdin and appends selected lines to any number of logs -- DJB
• multitail - Monitor multiple log files in a single terminal window -- C
• netconsole - Kernel module that sends kernel log messages (dmesg, etc) to a remote system without using syslog -- C
• NXLOG - Universal log collector and forwarder, supports many formats/platforms/sources including Windows -- C Windows
• Open Distro for ElasticSearch - Distro of ElasticSearch with all of the enterprise-grade features added in -- Java
• Open Web Analytics (OWA) - Track and analyze how people use your websites and applications -- PHP
• Promtail - Log shipper for Loki users -- Golang
• Sentry - Application exception logging -- Python
• Snoopy Logger - Logs commands that are executed and saves the information to syslog -- C
• Snowplow - Web, mobile and event analytics -- Scala
• swatch - Simple log watcher -- built-in

Metrics and Time Series Data

Collection, analysis, and storage of metrics, telemetry, and instrumentation data from almost any source - see also Dashboards and Data Visualization and Monitoring and Alerting and Logging

• collectd - Collects system performance statistics -- C
• collectd Related Sites - Great tools that integrate with collectd -- collection
• collectl - sar on steroids -- C
• Cortex - Multitenant, horizontally scalable Prometheus as a Service -- Golang
• Diamond - Python daemon that collects system metrics and publishes them to Graphite (or similar), has an API -- Python
• dim_STAT - Collects almost everything and stores it in a MySQL database, produces reports too -- C
• FastForward - Flexible system event and metric forwarding agent by Spotify -- Ruby gem
• Ganglia - Focused on HPC / distributed clusters, uses RRD -- various lang
• Graphite - Store numeric time-series data and render graphs of the data on demand -- Python
• Graphite Tools - Tools that work with Graphite -- collection
• Heka / hekad - Stream processing, can gather logs or performance metrics, by Mozilla, based on Borgmon -- Golang
• InfluxDB - Distributed time series database with no external dependencies -- Golang
• jmxtrans - Connector between speaking to a JVM via JMX and whatever stats / TSDB you use -- Java
• KairosDB - Time series DB written on top of Cassandra -- Java
• m3 - Distributed TSDB and query dngine, Prometheus sidecar and metrics platform by Uber -- Golang
• Metricbeat - fetches a set of metrics on a predefined interval from OS & services and ships them to Elasticsearch or Logstash -- Golang
• Metrics - Metrics and instrumentation at both the JVM and application level -- Java
• Micrometer - Provides a simple facade (fake interface) over the instrumentation clients for the most popular monitoring systems, allowing you to instrument your JVM-based application code without vendor lock-in -- Java
• mtail - Extract monitoring data from application logs for collection into a timeseries database, by Google -- Golang
• OpenTSDB - Store and serve massive amounts of time series data without losing granularity -- Java
• Prometheus - Metrics collection and storage, can trigger alerts when thresholds are breached, based on Borgmon -- Golang
• prometheus-am-executor - HTTP server that receives alerts from the Prometheus Alertmanager and executes a given command with alert details set as environment variables -- Golang
• Sensu Go - Open source monitoring framework, cloud-focused, dynamic, scalable - also does metrics collection -- Ruby
• SNMPcollector - SNMP collector that saves into InfluxDB for easy visualization -- Golang JavaScript
• SNMP MIB Archive - Massive archive of SMMP MIBs, please fork and contribute -- collection
• StatsD - Network daemon that listens for stats/counters/metrics and sends them to backend services (TSDB, Graphite, etc), by Etsy -- JavaScript
• Telegraf - Agent for collecting, processing, aggregating, and writing metrics -- Golang
• Thanos - Highly available Prometheus setup with long term storage capabilities -- Golang
• TimescaleDB - PostgreSQL extension for time series ingestion and queries via SQL -- C
• Whisper - Store time series info in regular file system files, a modern RRD -- Python

Monitoring and Alerting

Monitor stuff, send alerts, wake you up - see also Metrics and Time Series Data and Logging and Data Visualization and Dashboards

• Adagios - Web based Nagios configuration interface -- HTML
• Alerta - Distributed and de-coupled, requires MongoDB -- Python
• Bosun - Monitoring and alerting system written by Stack Exchange, based on Borgmon -- Golang
• Cabot - Self-hosted, easily-deployable monitoring and alerts service - like a lightweight PagerDuty -- Python
• check_mk - New Open Monitoring Distro, extensions / plugins for Nagios -- C
• Daemon Tools - Service monitoring and management tools -- DJB
• FastForward (ffwd) - Flexible system event and metric forwarding agent by Spotify -- Ruby gem
• health - An easy to use, extensible health check library for Go applications -- Golang
• Icinga - Nagios fork, updated frequently -- various lang
• Icinga2 - Complete re-write of Icinga by the same folks -- various lang
• LibreNMS - GPL fork of Observium -- various lang
• Monit - Includes tools to automatically take action when certain conditions are met (eg: restart a process when it dies) -- C
• Monitorix - So lightweight that it can be used in mobile devices, aka Mikaku -- perl
• Naemon - Modular Nagios fork -- various lang
• Nagios - One of the most widely used OSS monitoring programs -- various lang
• Nagios Exchange - Centralized repository of Nagios plugins, addons, extensions, etc -- collection
• NetXMS - Monitoring for all types of devices across the entire data center (hosts + network devices) -- C
• OpenNMS - Network monitoring, also supports configuration/asset management -- various lang
• pmacct - IP and network traffic accounting / monitoring -- C
• PHP Server Monitor - Simple monitoring package that can use built-in public SMS gateways for notifications -- PHP
• Sensu Go - Open source monitoring framework, cloud-focused, dynamic, scalable - also does metrics collection -- Ruby
• Sensu Plugins - Official community site for Sensu plugins -- various lang
• Shinken - Nagios-compatible monitoring, supports high availability -- Python
• Statping - THE BEST simple all in one monitoring solution, with mobile app, great for home/small networks -- OMG
• Uptime - Remote monitoring application using Node.js, MongoDB, and Twitter Bootstrap -- JavaScript
• Xymon - Fork of Big Brother -- C
• Zabbix - Stores monitoring data in a DB, has agents for almost every OS, can be a virtual appliance -- various lang
• Zenoss Core - Supports Nagios plug-in format, based on the Zope application server -- Python

Networking Tools

Hodge-podge of network tools - see also Security Tools and Network Performance Analysis Tools and Orchestration for parallel SSH tools

• 2ping - Simple bi-directional ping utility, helps determine where packet loss occurs -- Python
• aria2 - CLI for downloading HTTP/HTTPS, FTP, SFTP, BitTorrent and Metalink -- C Windows OS X
• ARIN WHOIS in JSON - Authoratative (official) info including CIDR and OriginAS, updated every 8h -- collection
• arp-scan - Create and send ARP requests -- C
• Awesome PCAP - Huge list of tools that work with PCAP captures -- collection
• bbcp - Copies files using multiple TCP streams to greatly increase throughput -- C
• BIRD Internet Routing Daemon (BIRD) - (Almost) fully functional IP routing daemon for Linux, supports tons of standard routing protocols -- C
• BPF Tools - BSD Packet Filter (BPF) and pcap toolkit, by CloudFlare -- Python
• CERT NetSA Security Suite - Network flow analysis tools -- various lang
• Cyberduck - GUI FTP, SFTP, WebDAV, S3 & OpenStack Swift browser for Mac and Windows -- itsaduck
• Data Plane Development Kit (DPDK) - Data plane libraries and framework for fast packet processing -- C
• dsniff - Great for level 2 analysis or service spoofing -- C
• ElastiFlow - Netflow collection and visualization using the ELK stack -- various lang
• ExaBGP - The BGP swiss army knife of networking -- Python pip
• Fast Data Transfer (FDT) - For writing at disk speed over WANs -- Java
• FBOSS (FaceBook Open Switching System) - FB's software stack for managing and controlling their internal switches -- various lang
• FreeZTP (Zero Touch Provisioning) - A Zero-Touch Provisioning system built for Cisco IOS -- Python
• FRRouting - Replacement for / fork of Quagga with more features -- C
• ftptop - Monitor FTP connections in real time -- built-in
• Gas Mask - Simple hosts file manager for Mac OS X, switch between host files easily -- Objective C
• kcptun - Secure and fast tunnel based on KCP -- Golang
• ipcalc - CLI tool to calculate subnets, netmasks, IP ranges, broadcast addresses, and more -- built-in
• iptstate - A top-like display of IP Tables state table entries -- built-in
• GridFTP - Supports parallel streams, optimized for WANs, part of the Globus Toolkit -- C
• hosts - Consolidates several reputable hosts files and merges them into a unified hosts file with duplicates removed (ads, malware, gambling, porn, etc) -- collection
• hping3 - Create custom TCP/IP packets, very flexible -- built-in
• joincap - Alternative to mergecap -- Golang
• lftp - Supports many protocols (FTPS, HTTPS, SFTP), scheduling, bandwidth throttling, scripting, and more - feature-rich -- C C++
• lldpd - Daemon that can talk LLDP aka the open version of Cisco Discovery Protocol (CDP), handy for network + host mapping -- C
• Manito Networks Flow Analyzer - ELK stack netflow analyzer -- Python
• moloch - Large scale IPv4 full PCAP capturing, indexing and database system -- JavaScript
• mrsync (multicast remote sync) - Transfers from a master to many remote machines using Unix multicast sockets -- C
• mTCP - High-performance user-level TCP stack for multicore systems -- C
• Multipath TCP Checker - Multipath TCP client tester -- in-browser
• My Looking Glass (myLG) - All-in-one CLI network diagnostic tool -- Golang
• NAPALM (Network Automation and Programmability Abstraction Layer with Multivendor support) -- Network automation and programmability abstraction layer, for both setting config and config validation -- Python pip
• ncat - Improved netcat, written by the Nmap team -- C
• Netconf - Web-based GUI for configuring API-less Cisco devices -- Python
• netsniff-ng - High performance, zero-copy networking sniffer -- C
• NETworkManager - All in one network GUI (config, troubleshooting, etc), neat! -- C Sharp
• ngrep - Network grep -- C built-in
• Nornir - Python automation framework without a DSL, alternative to managing network devices with Ansible -- Python
• nping - Create custom network packets -- C
• OpenBGPD - Free implementation of BGP v4 -- C
• OpenBMP - BGP Monitoring Protocol collector with real-time monitoring, looking glass, analytics, etc -- various lang
• OpenOnload - User-land network stack that requires no modifications to applications to use by intercepting calls -- C
• OpenWRT - Full Linux distro for consumer-grade routers, allows for tons of non-vendor customization -- various lang
• PFQ - Framework that allows efficient packets capture/transmission, in-kernel functional processing, and packets steering across sockets/end-points -- C
• PowerAdmin - Simple Web UI for PowerDNS -- PHP
• Quagga - Routing software suite, supports most routing protocols -- C
• SiLK (System for Internet-Level Knowledge) - Tool suite supports the efficient collection, storage, and analysis of network flow data, enabling network security analysts to rapidly query large historical traffic data sets -- C
• snabb - Worth seeing -- various lang
• socat - netcat on steroids, supports serial devices -- C
• sslh - Protocol multiplexer, let multiple daemons listen on a single port -- C
• tcpflow - TCP demultiplexer, each flow is stored in it's own file -- C++
• tcpreplay - Capture, edit, and replay network traffic -- C
• tracepath - Traceroute that doesn't require root -- C
• vFlow - High-performance, scalable and reliable enterprise netflow collector with Kafka integration, by Verizon -- Golang
• webterm appliance - Debian-based networking toolbox, runs in a Docker container + Firefox, by the GNS3 team -- neat
• WireShark - The classic network analyzer -- C
• WireShark Tools - Superb list of network tools from the WireShark wiki -- collection
• Zenmap - Official GUI for Nmap -- C Windows OS X

Network Performance Analysis Tools

Load generation, benchmarking, profiling, and latency simulation tools for TCP/IP networks - see also Web and HTTP Performance Analysis Tools and Performance Analysis Tools

• ARGUS (Audit Record Generation and Utilization System) - Generates network activity reports -- C
• bmon - Console based network monitor -- C
• clumsy - Simulate poor network conditions on Windows -- C Windows
• Comcast - Simulate crappy network connections -- Golang OS X
• ESnet Fasterdata Knowledge Base - Provides proven, operationally sound methods for troubleshooting and solving performance issues -- collection hpcwisdom
• EtherApe - Graphical network monitor, pretty output -- various lang
• Flent - Python wrapper to run mutliple netperf/iperf3/ping in parallel, formerly netperf-wrapper -- Python
• Flowgrind - Distributed TCP traffic generator -- C
• iftop - top for network interfaces -- C
• iperf3 - Supports tuning of various parameters related to timing, protocols, and buffers -- C
• iptraf-ng - Updated fork of iptraf -- C
• jnettop - Terminal / ncurses traffic visualizer -- C
• mtr (my traceroute) - Combines ping and traceroute into a single program -- C
• Muxy - Muck with your system and application context layers 4-7 -- Golang OS X
• namebench - Hunts down the fastest DNS servers for your computer to use -- Python Windows OS X
• netatop - Kernel module for atop to watch and report on network packets -- C
• netem - Network emulator for testing variable delay, loss, duplication and re-ordering -- C
• NetHogs - Displays per-process bandwidth usage -- C C++
• Network Link Conditioner - Simulate bandwidth, latency, and packet loss, by Apple -- closed source OS X
• nfdump - Captures network flows including sFlow, NetFlow, NetFlow v9, ipfix, etc -- perl
• nicstat - vmstat for network interfaces -- C
• nload - Console application that monitors network traffic and bandwidth usage in real time, neat ASCII graphs -- C++
• ntopng / ntop-ng - New version of the popular ntop tool -- C
• netperf - Network load generator, by HP -- C
• Paris Traceroute - Shows proper network topology when load balancers and load-balanced routers are used -- C
• Ruru - Real-time TCP latency monitoring, utilises Intel DPDK for high speed packet processing with a Node.JS frontend for visualizing the data -- various lang
• SmokePing - Network latency visualizer, written by the MRTG and RRDtool guy -- perl
• ss - Socket statistics, a modern netstat -- built-in
• Stanford Linear Accelerator Center - Network Monitoring Tools - MASSIVE list of network monitoring tools -- collection
• tc - Built-in Linux kernel traffic control -- built-in
• TCP Throughput Calculator - See name -- in-browser
• tcpdive - TCP performance analysis tool, implemented as SystemTap scripts -- C
• tcptrack - Console based connection tracker -- built-in
• trickle - Userspace bandwidth shaper -- built-in
• vnStat - Console based traffic monitor, supports statistic collecting -- C
• WinMTR - Windows GUI for MTR -- C++
• Yconalyzer - Monitor and analyze TCP connections -- C++

Orchestration

OS and VM level orchestration as well as parallel SSH tools - see also Containers and Distributed Systems Tools for container orchestration and Terminal Tools and SSH Clients for SSH clients and SSH Tools for misc SSH tools and Provisioning Tools

• Ansible - CM and orchestration, also can do provisioning -- Python
• Batou - Define and perform automated service deployments -- Python pip
• Capistrano - Use Ruby to run scripts/commands and push software via SSH, uses a Rake DSL -- Ruby gem
• ClusterSHISH - Cluster SSH for Windows, works with PuTTY and OpenSSH for Windows -- closed source Windows
• ClusterSSH - Make a change on many servers at the same time -- perl
• csshX - Cluster SSH for OS X -- C
• KeyBox - Web-based SSH console that executes commands on multiple shells simultaneously and supports terminal sharing -- Java
• KeyBox-OpenShift - KeyBox for OpenShift gears -- Java
• Mass Parallel SSH (mpssh) - Simple parallel SSH -- C
• Multipass - Super light weight VM manager, easy way to get a fresh Ubuntu machine -- C++
• OpenLMI (Open Linux Management Infrastructure) - Manage, monitor, and configure servers via API calls (instead of SSH), included in RHEL 7 -- various lang
• orgalorg - Next generation parallel SSH tool because most other major ones are no longer maintined -- Golang
• parallel - Execute jobs in parallel using one or more computers -- built-in
• parallel-ssh (pssh) - Parallel version of OpenSSH tools - comes with prsync, pscp, pnuke, and pslurp too -- Python built-in
• Parallel Distributed Shell (pdsh) - Kick off many SSH sessions in parallel -- C
• PyDSH - Python Distributed Shell, parallel SSH -- Python
• Rundeck - Job scheduler and runbook automation, enable self-service access to existing scripts and tools -- Groovy
• Salt / Saltstack - Orchestration, server provisioning, and configuration management -- Python
• Spacewalk - Remote commands/orchestration, patch management, and more - the upstream for Red Hat Satellite 5.x and earlier -- various lang
• Teleport - Front-end for teams, includes session capture and replay, auditing, 2FA, session sharing, and more -- Golang
• tmux-cssh - Cluster SSH via tmux -- shell
• xCAT (Extreme Cloud Administration Toolkit) - Complete all in one management solution (provisioning, orchestration, management, etc) supports almost every UNIX and next generation platform, by IBM -- legit

Package Patch and Repository Tools

Repos, RPM/APT packages, packaging guidelines, patching, and patch management - see also Provisioning Tools

• apt-dater - Simple ncurses frontend for package management via SSH, also supports yum -- C
• aptly - Swiss army knife for Debian repository management, has the ability to take snapshots for easy rollback -- C
• AutoPkg - Packaging and distribution for OS X, great for managing many laptops -- Python OS X
• CentOS Errata for Spacewalk (CEFS) - Import errata information from CentOS-announce into Spacewalk -- useit
• CentOS Repositories - Large list of both official and unofficial CentOS software repositories -- collection
• CentOS Software Collections (SCL) - Use multiple versions of software on a system without disturbing the system default version -- C
• Copr - Automatic build system providing a package repository as its output, by Fedora -- C
• cowbuilder - Package builder that uses copy-on-write (COW) to speed up the build process -- C
• DNF aka Dandified yum - yum v4 packaging system, added to upcoming Fedora/RHEL/CentOS 8 releases -- article
• ELRepo - Repo that focuses on hardware related packages, supports RHEL and CentOS -- repo
• Extra Packages for Enterprise Linux (EPEL) - Supports CentOS, RHEL, Scientific Linux, and Oracle Linux -- repo
• Extra Packaging Guidelines and Policies for EPEL - Packaging guidelines, great even if not creating EPEL stuff -- readit
• Fedora Packaging Guidelines - Excellent information that can be applied to CentOS & RHEL -- readit
• fpm (Fucking Package Management) - Build packages for multiple platforms (deb, rpm, etc) with great ease and sanity -- Ruby gem
• fpm-cookery - Tool for building software packages with FPM -- Ruby gem
• Habitat - Creates platform-independent build artifacts and provides built-in deployment and management capabilities -- Golang
• Homebrew (aka brew) - Tons of packages for Mac -- Ruby OS X
• Koji - Software that builds packages for Fedora, can be used for other stuff too, uses mock -- C
• Mock - Build packages in a simple chroot so you don't blow up your system -- C
• mrepo - RPM repository management tool supporting ftp/http/sftp/rsync/rhn/you, formerly Yam -- Python
• Munki - Managed software installation for OS X, great for managing laptops -- Python OS X
• OStree - Tool for managing bootable, immutable, versioned filesystem trees (not really a package manager but...) -- thefuture C
• pkgr - Made deb or RPM packages out of any Ruby, NodeJS, or Go app -- Ruby
• Pulp - Next generation repository management, a component of Red Hat Satellite 6 -- Python
• Red Hat Software Collections (SCL) - Use multiple versions of software on a system without disturbing the system default version, use this to get the newest / latest versions of things -- repo
• reposync - Synchronize yum repositories to a local directory -- built-in
• rpm-ostree - Hybrid image/package system with atomic upgrades and package layering -- C thefuture
• RPM Fusion - Provides software that the Fedora Project or Red Hat doesn't ship -- repo
• schroot - Allow non-root users to create chroot environments, great for package testing -- built-in
• Spacewalk - Patch management, remote commands, and more - the upstream for Red Hat Satellite -- various lang
• Tito - Tool for managing RPM based projects using git for their source code repository -- Python
• yum-presto - yum plugin that provides support for downloading package deltas -- article
• yum-security - Plugin to only install security updates -- built-in

Performance Analysis Tools

Non-specific and all-in-one performance monitoring tools - see also web, network, storage, and RDBMS and Tracing and Profiling

• atop - Supports both real-time and historical performance monitoring -- C
• Conky - Lightweight system monitor for X windows -- C++
• Glances - Real-time performance monitoring, written in curses and Python -- Python
• hazelnut - Python lib to parse /proc/meminfo -- Python pip
• htop - top replacement, has a few additional features -- C
• Linux Performance Observability Tools - Awesome graphic that shows you which tool to use, by Brendan Gregg -- yells at drives
• mem_logger.sh - Monitor a processes' memory usage over time -- shell
• Munin - Historical performance monitoring to help determine when you server became "slow" -- perl
• NetData - Real time performance visualization and dashboards -- C
• nmon - Provides both real-time and historical performance metrics -- C
• NumaTOP - top for NUMA systems, shows hotspots, call chains, etc -- C
• PerfKit Benchmarker - Open effort to define a canonical set of benchmarks to measure and compare cloud offerings (disk, network, CPU, etc) -- various lang
• Phoronix Test Suite - Benchmarking and profiling suite, very feature-rich and versatile -- PHP
• pidstat - vmstat type output for CPU, disk I/O, page faults, and more on a per-process basis -- built-in
• pmap - Shell scripts for tracking memory usage using "pmap" -- shell
• PowerTOP - Real-time power consumption on a per-process & per-thread basis, by Intel -- C++
• ps_mem - Accurately reports core memory usage for a process -- Python
• ptop - top/ntop-like task monitor written in Python -- Python pip
• recap - Collects info from various standard utilities (free, sar, vmstat, etc) at specified intervals, by Rackspace -- various lang
• saidar - ncurses based program for viewing system statistics -- built-in
• slabtop - Tutorial on how to use slabtop, useful when you have no idea on how your RAM is being used -- article
• smem - Reports memory usage based on proportional set size (PSS) instead of the usual resident set size (RSS) -- C
• sysdig - Linux system exploration and troubleshooting tool with first class support for containers -- C++
• VMtouch - File system cache diagnostics and control -- C

Provisioning Tools

OS provisioning, image creation, installation, bootstrapping, and lifecycle management - see also Package Patch and Repository Tools and Containers and Distributed Systems Tools and Live CD Tools

• Atlantis - A unified workflow for collaborating on Terraform through GitHub and GitLab, by Hootsuite -- Golang
• Box-Cutter - Hashicorp's community repo for Packer & Vagrant templates -- Ruby
• Clonezilla - Disk image/cloning tool, supports most file system types -- perl shell
• cloud-init - Configures settings the first time a system spins up (SSH keys, hostname, variables, etc), note NoCloud -- C
• Fog - Computer / OS cloning tool, also has remote client management capabilities -- C++
• Foreman - Provisioning and life cycle management -- Ruby Windows OS X
• iPXE - GPL'ed version of PXE, official replacement for gPXE -- C
• Kickstart - The classic Red Hat tool -- various lang
• kitchen-terraform - Test Kitchen plugins for testing Terraform configurations with InSpec -- Ruby gem
• netboot.xyz - Simple iPXE menu and installer -- shell
• Packer - Automates VM creation for multiple platforms (VMware, AWS, etc) -- Golang
• Terraform - Infrastructure provisioning using existing tools, supports many providers (AWS, Azure, DO, OpenStack, etc) -- Golang Hashicorp
• Terraformer - Generate terraform files from existing infrastructure (reverse Terraform), supports AWS and GCP, by Google -- Golang
• Terraform CDK - Use TypeScript or Python to generate Terraform config files -- Golang
• Terraform Landscape - Makes terraform plan easier to read -- Ruby
• Terragrunt - Tools for keeping your Terraform configurations DRY, working with multiple Terraform modules, and managing remote state -- Golang
• Terratest - Makes it easier to write automated tests for your infrastructure code, provides a variety of helper functions and patterns for common infrastructure testing tasks -- Golang
• tflint - Terraform linter for detecting errors that can not be detected by terraform plan -- Golang
• Vagrant - Quickly spin up environments for local testing and development -- Ruby
• Vagrant Plugins - A list of Vagrant plugins on the official Hashicorp wiki -- collection
• Vagrant Manager - GUI to manage Vagrant boxes -- Windows OS X
• vagrant-cachier - Cache BLOB downloads to reduce network usage -- Ruby
• vagrant-host-shell - Simple plugin to run commands on the VM when it boots (think cloud-init) -- Ruby
• vagrant-hostsupdater - Plugin to add your own /etc/hosts to the VM -- Ruby
• vagrant-vbguest - Auto-install the latest VirtualBox tools at boot time (if necessary) -- Ruby
• Salt / Saltstack - Orchestration, server provisioning, and configuration management -- Python

Python Tools and Resources

Python stuff of note

• argparse - Parser for command-line options, arguments and sub-commands -- Python
• atexit - Exit handlers -- Python
• Awesome Python - Very large list of Python resources -- collection
• bpython - Killer interface for the Python interpreter -- Python
• Celery - Async task/job queue based on distributed message passing -- Python
• ciscoconfparse - Parse, audit, query, build, and modify Cisco IOS-style configurations -- Python pip
• Collections - High-performance container data types -- Python
• exscript - Write less code using than either pure paramiko or netmiko -- Python
• Fabric - Uses paramiko to implement a higher-level API for performing commands over SSH, particularly for deployment sysadmin tasks -- Python pip
• Faker - Generate fake data easily -- Python pip
• Fire - Turn any Python module, class, object, function, etc into a CLI -- Python
• functools - Higher-order functions and operations on callable objects -- Python
• FunkLoad - Functional and load web tester -- Python pip
• getpass - Enter a password without echoing what they type to the console -- Python
• Google Python Style Guide - Google's Python style guide -- article
• inspect - Inspect live objects -- Python
• IPython - Interactive Python shell and the kernel for Jupyter -- Python
• Itertools - Functions creating iterators for efficient looping, iterator building blocks -- Python
• Jinja2 - Templating language for Python -- Python pip
• Jupyter - The language-agnostic parts of IPython -- Python
• Logging - Flexible event logging system for applications and libraries for all modules and more -- Python
• Mailer - The best e-mail module -- Python
• more-itertools - More routines for operating on iterables, beyond itertools -- Python pip
• netaddr - A network address manipulation library for Python -- Python
• netmiko - Multi-vendor library to simplify Paramiko SSH connections to network devices -- Python
• netminko_tools - Command line tools built on Netmiko to simplify information gathering -- Python
• os - Interact with the OS -- Python
• paramiko - SSH2 protocol library for Python, provides both client and server -- Python pip
• pdb - Python debugger -- Python
• pexpect - Expect-like module -- Python
• pycsco - Python modules to simplify the use of working with Cisco Nexus switches -- Python
• PyEnv - Simple Python version management that keeps everything within your home directory, virtualenv alternative -- shell
• Pynag - Interface with Nagios via Python -- Python pip
• PyPI (Python Package Index) - Software repo for Python packages, like Ruby gems or a RPM repo -- collection
• PyPy - Python alternative with advance features (JIT compiles, sandboxing, etc) -- Python
• python-prompt-toolkit - Library for building interactive command lines -- Python pip
• Python Patterns - Python patterns by Brandon Rhodes -- collection
• RadSSH - Paramiko-based parallel SSH -- Python pip
• Requests - The best HTTP library -- Python pip
• scapy - Interactive packet manipulation for Python -- Python pip
• selenium - Browser automation -- Python
• sh - Library that allows you to call any program (shell command) as if it were a function -- Python pip
• Subprocess - Spawn subprocesse and collect their output -- Python
• sys - System-specific parameters and functions -- Python
• TCPWatch - TCP monitoring and logging tool -- Python pip
• tempfile - Generate temporary files and directories -- Python
• TextFSM - Create a pool of templates to parse text, then use TextFSM to parse useful information from a variety of sources -- Python
• urllib - Open, read, parse URLs and robots.txt -- Python
• virtualenv - Tool to create isolated Python environments -- Python pip
• virtualenvwrapper - Extensions to virtualenv -- Python pip
• wtfpython - A collection of surprising Python snippets and lesser-known features -- collection
• xlwings - Replace your Excel VBA code with Python -- Python pip

Python Programming Tutorials

Tutorials, exercises, and challenges for learning Python. I have no idea how good/bad these are

• 500 Lines - Many full Python programs written in 500 lines or less, great for beginners
• CheckiO - Challenges, shows all submitted solutions to a challenge and people vote for best - great way to see each POV -- in-browser
• Codecademy - Codecademy's online Python course
• CodingBat - Practice problems
• Coursera - Online Python courses at various institutions
• Dive Into Python 3 - Free ebook
• edX - Python courses at edX
• Google Python Class - By the GOOG
• importpython's Python Book List - Includes both free and pay, ebooks and physical
• Intermediate Python - Free ebook
• Invent with Python - Series of free ebooks, includes Automate the Boring Stuff with Python, recommended books
• Learn Python, Break Python - Free ebook
• MIT Open Courseware - Introduction to Computer Science and Programming - Focuses on Python
• MIT Open Courseware - A Gentle Introduction to Programming Using Python - Final project is a Tetris game in Python
• MIT Open Courseware - Objects in Python - Python tuples, lists, and dictionaries, as well as the concept of mutability and how to avoid problems relating to it.
• MIT Open Courseware - Python Tutorial - Python tutorial for people familiar with basic programming concepts
• New Coder - Python exercises
• Online Python Tutor - 100% in-browser
• Programming Praxis - Programming exercises, many posted solutions are in Python
• Python Challenge - A riddle in Python
• Python for Infomatcis - Free ebook
• Python for You and Me - The 2.x version is linked on the main page
• Python Practice Projects - Several practice exercises
• Python 2.x Tutorial - For 2.x, part of the official documentation
• Python 3.x Tutorial - From the official documentation
• Quiz and Learn Python - Designed for mobile devices
• r/dailyprogrammer - Programming exercises, includes Python
• r/learnpython - Subreddit for beginners, be sure to check the wiki too
• Supporting Python 3 - Free ebook that focuses on porting to Python 3.x
• Think Python: How to Think Like a Computer Scientist - Awesome free ebook
• Tutorials Point's Python Tutorial - Another one!

RDBMS and SQL Tools

Tools for interacting with and related to the major DBs and SQL

• Adminer - GUI for database management in a single PHP, formerally phpMyAdmin -- PHP
• CockroachDB - Open source version of Google's Spanner storage system -- thefuture Golang
• DBeaver - OSS multi-platform GUI that supports almost every DB, built from Eclipse -- Eclipse
• DB Browser for SQLite - GUI database browser for SQLite instances -- C++
• Flyway - Version control for DB schemas, supports most DBs -- Java
• gh-ost - Online schema migrations for MySQL, by GitHub -- Golang
• HeidiSQL - GUI SQL DB browser and editor -- Windows OS X
• Liquibase - Tracking, managing, and applying database schema changes, SVN for DBs -- Java
• MaxScale - General purpose DB query proxy, router, and load balancer by MariaDB -- C
• mycli - CLI for MySQL and derivates with auto-completion and syntax highlighting -- Python
• mydumper (MySQL Data Dumper) - Much better than mysqldump, works in parallel -- perl
• MyRocks - RocksDB with a MySQL front-end / interface -- C++
• MySQL sys schema - Collection of views, functions and procedures to help MySQL administrators get insight into MySQL usage -- SQL
• MySQL Workbench - The official MySQL GUI for admins, devs, DBAs, and architects -- various lang
• Oracle TPT Scripts - Tanel Poder's Troubleshooting & Performance Tools for Oracle Databases -- SQL
• orchestrator - MySQL replication topology management and visualization tool, GUI -- Golang
• Percona Toolkit for MySQL - Percona's special toolkit -- various lang
• pgcli - Postgres CLI with autocomplete and syntax highlighting -- Python
• pgloader - Fast data loader for PostgreSQL -- Lisp
• pgweb - Web-based PostgreSQL DB browser -- Golang
• pg_repack - Remove bloat from tables and indexes without using an exclusive lock -- C
• Phinx - Database migrations in SQL or PHP -- PHP
• Postgres-XL - Scale-out version of PostgresSQL -- C
• Postgres.app - All-in-one version of Postgres for local testing on a laptop -- C
• PostgREST - Create a REST API for any Postgres DB -- Haskell
• PostgreSQL GUI Tools - A huge list on the official wiki -- collection
• Presto - Distributed SQL query engine for big data, by Facebook -- Java
• Sequel Pro - MySQL management GUI for Mac -- OS X
• shift - Schema migrations for MySQL, by Square -- Ruby
• SQLite - Self-contained, serverless, zero-configuration, transactional SQL database engine, great for testing -- C
• sqlmap - Detect and exploit SQL injection flaws, pen testing tool -- Python
• SQL Fiddle - Write and test SQL -- in-browser
• wal-e - Simple continuous archiving for PostgreSQL -- Python
• WWW SQL Designer - Designing RDBMS schemas features saving, exporting to XML, and SQL script creation, free SaaS version here -- JavaScript

RDBMS Performance Analysis Tools

Load generation, benchmarking, telemetry, and profiling for various RDBMS platforms - see also Storage Performance Analysis Tools and Performance Analysis Tools and Tracing and Profiling and Network Performance Analysis Tools and Metrics and Time Series Data

• HammerDB - Load testing and benchmark tool, supports most DBs -- Tcl
• innotop - "top" for MySQL -- NOTE: beware of exposing your password -- perl
• MySQLtuner-perl - Analyzes a MySQL installation and provides suggestions to increase performance -- perl
• MySQL Performance Analyzer - Open sourced by Yahoo -- Java
• Open PostgreSQL Monitoring (OPM) - Includes a web console, nice GUI -- JavaScript
• Percona Toolkit for MySQL - Percona's internal tools -- various lang
• pg_activity - htop for PostgreSQL -- Python
• pg_view - PostgreSQL monitoring, supports ncurses, console, and JSON output -- Python pip
• pgBadger - PostgreSQL log analyzer -- perl
• PgHero - A performance dashboard for Postgres - health checks, suggested indexes, and more -- JavaScript
• PGObserver - Killer PostgreSQL monitor, includes dashboard -- Python
• Silly Little Oracle Benchmark 2 (SLOB2) - Stresses and benchmarks Oracle DBs, works at the RDBMS layer -- various lang
• Swingbench - Oracle load generator -- closed source
• SysBench - Evaluates OS parameters that are important for DBs, does not require a DB to be installed -- C
• Tsung - Distributed stress tester, also supports stress testing DBs -- Erlang

Regular Expressions

regex checkers, creators, evaluators, debuggers, and tutorials - see also Shell Scripting and Tools and Software Development Tools

• Debuggex - Online regex debugger -- in-browser
• ExtendsClass - Online visual regex tester -- in-browser
• perlretut - perl-focused but very useful for all regex -- article
• Refiddle - Online, supports JavaScript, Ruby, and .NET only -- in-browser
• regex101 - Online regex tester and debugger, supports multiple languages -- in-browser
• RegexOne - Learn regular expressions with simple, interactive examples -- tutorial
• regexper - Regex visualizer using railroad diagrams, great for debugging -- in-browser
• RegExr - Another online regex tool that includes cheat sheets, examples, and community-contributed expressions -- collection
• RegularExpressions.info - THE BEST regex site -- collection
• Regular Expressions - A Gentle User Guide and Tutorial - The easy way -- tutorial
• RexV.2 - Online Regex evaluator, supports multiple languages -- in-browser
• Rubular - Online Ruby-only regex evaluator -- in-browser
• txt2re - Regex generator, recommended -- in-browser
• txt2regex - Converts human sentences to regex, written in bash -- shell

Secrets Management

Password, private key, and API key storage and management tools - see also Security Tools and SSL Tools and Two Factor Authentication and VPNs and Tunnels

• Bitwarden - The new hotness in password management -- various lang
• blackbox - Safely store secrets in Git, by Stack Exchange -- shell
• Diceware - Neat IRL passphrase generator -- doitirl
• encpass - Lightweight solution for using encrypted passwords in shell scripts -- shell
• GPG (GNU Privacy Guard) - The original! Store em in text files and encrypt -- C pro
• GRC Password Generator - Generates 63 bit passwords -- in-browser
• Kee - Auto-fill website logins using KeePass as a source, like LastPass -- C# Firefox
• Keybase - Upload your public key and find other people's public key via their social media user name(s) -- in-browser
• KeePass - Lightweight, easy to use, GUI password manager, runs on most platforms -- C# Windows
• Keepass2Android - Compatible with KeePass 2.x -- Android
• KeePassDroid - Open source version of KeePass 1.x for Android -- Android
• KeePassXC - Supports YubiKey and TOTP, forked becasue KeePassX is no longer being updated -- C++
• KeeWeb - Cross-platform password manager compatible with KeePass -- JavaScript
• Keywhiz - A system for distributing and managing secrets (API keys, certificates, etc), by Square -- Java
• kpcli - Command line interface / CLI for KeePass -- perl
• lastpass-cli - CLI for LastPass -- C
• MacPass - A free, open-source, KeePass-compatible password manager for macOS -- Objective-C
• msktutil - Keytab client for a Microsoft Active Directory environment -- built-in
• One-Time Secret - Create links that self-destruct after a single viewing, great for sharing passwords -- Ruby
• pass (passwordstore) - Uses GPG at it's core, supports tracking password changes in git -- shell
• passff - Addon for interacting with the a pass aka passwordstore repository -- Firefox
• Password Pusher - Links to passwords expire after a certain number of views and/or time has passed, RoR app -- Ruby
• Password Safe - Designed by Bruce Schneier himself -- bam
• pwd.sh - Script to manage passwords in an encrypted file using GPG -- shell
• pwgen - Password generated, included in most Linux distros -- built-in
• Secrets OPerationS (SOPS) - Secrets management, by Mozilla -- Python
• TeamPass - Collaborative password management using the LAMP stack -- PHP
• Vault - Tool for storing secrets (API keys, passwords, certs, etc) by Hashicorp -- Golang

Security Tools

Misc security tools - see also Live CD Tools and Networking Tools and Secrets Management and SSL Tools and Two Factor Authentication and VPNs and Tunnels and Logging

• Advanced IP Scanner - For Windows, recommended -- closed source
• afl-fuzz (American Fuzzy Lop) - One of the best fuzzers -- C
• AIDE (Advanced Intrusion Detection Environment) - File integrity checker, alternative to Tripwire -- various lang
• Amass - Automatically obtains subdomain names in a variety of ways and uses that info to build maps of the target network, by OWASP -- Golang
• Angry IP Scanner - GUI network scanner, supports plugins, -- Java Windows OS X
• Armitage - GUI for Metasploit -- Java
• ATA Secure Erase - Send a signal to an ATA drive to perform a hardware-based erase, the ONLY way to wipe a SSD properly -- article
• Attack Surface Analyzer 2.0 - See exactly what changed post-OS install or post-software install, by Microsoft -- Windows
• auditd-attack - A Linux Auditd rule set mapped to MITRE's Attack Framework -- collection
• authconv - Web app authorization coverage scanning -- JavaScript
• Awesome Honeypots - Curated collection of honepots and honeypot resources -- collection
• bettercap - Swiss Army knife for 802.11, BlueTooth, and Ethernet networks reconnaissance and attacks -- Golang
• Brida - Bridge between Burp Suite & Frida, lets you use and manipulate applications own methods while tampering the traffic exchanged between the applications and their back-end services/servers -- various lang
• bro - Framework for network analysis and security monitoring -- C++
• CALDERA - Automated adversary emulation system that performs post-compromise adversarial behavior within Windows Enterprise networks -- Python
• Checkov - Scans cloud infrastructure provisioned using Terraform, Cloudformation or Kubernetes and detects security and compliance misconfigurations -- Golang
• cherrytree - Hierarchical note taking application, excellent for red team / pentest notes -- Python
• chkrootkit - Rootkit checker, best used from a live CD -- C
• CIS Linux Benchmarks - Linux OS hardening guides, superb! -- collection
• Common Vulnerability Scoring System Calculator - Version three -- collection
• ConfigServer Security and Firewall (CSF) - Stateful Packet Inspection (SPI) firewall, Login/Intrusion Detection and Security application for Linux servers -- various lang
• CSP Evaluator - Check if a Content Security Policy (CSP) serves as a strong mitigation against cross-site scripting attacks, by Google -- in-browser
• cuckoo - Feed in malware URL, it fires up VM, and provides a report about the actions the malware took -- in-browser
• CyberChef - A web app for encryption, encoding, compression and data analysis -- in-browser JavaScript
• Cyber Security Transformation Chef - CyberChef as a Burp Suite extension -- Java
• dcfldd - Enhanced dd with security and forensics features -- C
• Dradis CE (Community Edition) - Reporting framework for generating one-click reports (vuln scanning, pentest, etc) -- Ruby
• Dshell - Network forensic analysis framework, written by the US Army -- Python
• EncFS - Encrypted file system in user space via FUSE -- C++
• fail2ban - Watches log files to ban IPs based on rules (too many failed logins, exploit attempts, brute force attacks, etc) -- Python
• Forensics Acquisition of Websites (FAW) - Download and save social media sites, paid version has more features -- closed source Windows
• Forensics Wiki - Digital forensics wiki, tons of tools and information -- wiki
• FTimes - System baselining and evidence collection tool -- C
• fwknop (FireWall KNock OPerator) - Single Packet Authorization (SPA), authoriation packet from you opens firewall rules so only you can get in -- various lang
• GGCR - GRC, by Google -- Python
• Google Safe Browsing Site Status - Use Google for site/URL malware analysis -- in-browser
• GRR Rapid Response - Live forensics for incident response via a Python agent, dump memory, isolate host, snoop syscalls etc -- Python
• hashcat - World's fastest CPU password cracker / password recovery -- C
• Hybrid Analysis - Dree malware analysis service that detects and analyzes unknown threats using a unique Hybrid Analysis -- in-browser
• icebreaker - Automates internal network attacks against Active Directory to deliver you plaintext credentials -- various lang
• Information Security Cheat Sheets and Checklists - An assortment of IS checklists and cheat sheets, -- collection
• Jenkins Pentesting - Title, please contribute -- various lang
• Just the Basics (JTB) Investigator - Simple menu & CLI to automate repetitive everyday tasks -- Python
• geoiplookup - Uses the GeoIP DB and library to determine which physical country an IP or host originates in, includes PAM library -- built-in
• Hindsight - Internet history forensics for Google Chrome/Chromium -- Python
• Jailkit - chroot toolkit -- C
• Joe's Sandbox (Cloud Basic) - Deep automated malware analysis -- in-browser
• Kali NetHunter Linux Root Toolkit (LRT) - Collection of bash scripts that setup and install Kali Linux NetHunter from a Linux/OSX environment onto a NetHunter supported device -- shell
• LinEnum - Enumerate a local Linux environment -- shell
• Lynis - Auditing and hardening tool, supports most Unix-like operating systems -- shell
• Malcom - Easily deployable network analysis tool suite for full packet capture artifacts (PCAP files) and Zeek logs -- various lang
• Massscan - Scans in parallel and async for the fastest scans around -- C
• Metasploit - Classic exploit framework -- various lang
• National Checklist Program - U.S. government repository of publicly available security checklists (or benchmarks) that provide detailed low level guidance on setting the security configuration of operating systems and applications -- collection
• National Software Reference Library (NSRL) - Large collection of diskprints from various software and malware -- collection
• National Vulnerability Database - Gotta catch em all -- collection
• Nikto2 - Web & app server vulnerability scanner -- perl
• nmap - Classic port scanner -- various lang
• nmap_vulners - Emumerate and list vulnerabilities during an nmap scan similar to Nessus -- collection
• nmap Scripting Engine (NSE) - Tons of scripts for nmap -- various lang
• oclHashcat - World's fastest CPU + GPU password cracker / recovery software -- C
• OpenSCAP - NIST Certified SCAP 1.2 toolkit -- C
• OpenVAS - Vulnerability scanner, forked from the now closed-source Nessus scanner -- C
• Open Web Application Security Project (OWASP) - Focus on web application security -- organization
• Oracle Database Attacking Tool (ODAT) - Open source penetration testing tool that tests the security of Oracle databases remotely -- Python
• OS X Auditor - Forensics tool for Mac -- OS X JavaScript
• OSSEC - Host based intrusion detection system (HIDS), supports most Unix-like OSes -- C Windows OS X
• OWASP Cheat Sheet Series - Contains all OWASP cheat sheets, new v2 -- collection
• PALADIN - Easy to use Linux-based live CD for forensic analysis -- various lang
• Penetration Testers Framework - Script to pull down all the latest greatest tools -- Python
• pfsense - The best firewall software, supports appliances and live CDs -- C
• preeny - Some helpful preload libraries for pwning stuff -- C
• Prey - Open source anti-theft software for almost all platforms -- shell Java mobile
• ProcDOT - All in one visual malware analysis and visualization, by CERN -- closed source various lang
• Purple Team ATT&CK Automation - Metasploit automation of MITRE ATT&CK TTPs -- Ruby
• Qubes OS - A reasonably secure operating system -- various lang
• Red October - Go server for two-man rule style file encryption and decryption -- way cool
• Red Teaming Toolkit - Collection of open source and commercial tools that aid in red team operations -- collection
• Regshot - Snapshot and compare the Windows Registry for before/after analysis -- C
• Rootkit Hunter - Compares hashes of important files with known good hashes that are stored in online databases -- perl shell
• SalSA (Salvaging Static Analysis) - Windows PE file parsing in-browser, can be locally hosted, by the DoD -- Python
• Samhain - HIDS, file integrity checker, rootkit detection, log file monitoring, and more -- C
• scrub - Supports many disk-wiping standards including military / government grade wipes -- built-in
• scrypt - More secure against hardware brute-force attacks than alternatives such as PBKDF2 or bcrypt, key stretching -- C
• SecLists - Collection of multiple types of lists used during security assessments collected in one place -- collection
• Security Onion - Linux distro for IDS, NSM, and log management -- various lang
• Security Technical Implementation Guide (STIG) - Guides to securing almost every application, by the US military -- collection
• SELKS - Debian based based IDS/IPS with ELK stack, installable or live CD -- various lang
• simplewall - Simple app to configure Windows Filtering Platform (WFP), VERY powerful -- Windows
• Snort - The classic network intrusion prevention system (NIPS) -- C
• SPARTA - GUI to simplify the scanning and enumeration phases -- Python
• Spiderfoot - Automate the process of gathering intelligence about a given target -- Python
• SubBrute - Subdomain enumeration tool for penetration testers -- Python
• sudosh2 - Records all keystrokes and output and can play back the session as just like a VCR -- C
• SuperTokens - OSS alternative to Auth0, Firebase Auth and AWS Cognito -- Java
• SWORD Dropbox -- $15 OpenWRT + Pi based DIY disposable pen-test tool -- various lang
• symon-config - Sysmon configuration file template with default high-quality event tracing -- XML!!!! Windows
• theZoo - These are real and they are smarter than you, do not fuck around -- collection
• tink - Smiple, small, secure crypto library by Google -- C++
• Tripwire - File integrity checker and monitor, replacement for the now closed-source Tripwire -- C
• URLquery - Free service to scan a URL for web-based malware -- in-browser
• urlscan.io - Similar to URLquery -- in-browser
• usbkill - Kill switch that takes action when a USB device is connected -- Python
• VeraCrypt - OSS successor to and fork of TrueCrypt, supports Linux, Windows, and Mac -- C C++
• VirusTotal - Allows you to upload a file and have it scanned by tons of virus scanners -- in-browser
• tcpbin - A simple TCP dumping server/host for pentesting -- Python
• Tomb - zsh wrapper script for cryptsetup + gpg + LUKS volumes -- shell
• URL Canary - Create canary URLs so you know if someone is inspecting the source code of your applications -- in browser
• VulnHub - ISOs and more for hands-on security practice -- collection
• w3af - Web application attack and audit framework, OSS vun scanner -- Python
• Zed Attack Proxy (ZAP) - Pen testing too that focues on web applications -- Java
• ZMap - Scanner designed for large address spaces -- in-browser
• zxcvbn - Password strength estimator, written by Dropbox, operates in a browser window -- CoffeeScript in-browser
• zzuf - Transparent application input fuzzer that works by intercepting file and network operations and changing random bits in the program's input -- C

Shell Scripting and Tools

Shell scripting tutorials, collections of note, Linux shells for Windows, and misc neat tools - see also Terminal Tools and SSH Clients and Orchestration for parallel SSH tools and Regular Expressions

• Advanced Bash-Scripting Guide - By the Linux Documentation Project (LDP) -- tutorial
• awk Tutorial - Easy to understand awk tutorial -- tutorial
• Awesome dotfiles - All kinds of . files -- collection
• autojump - Small database of directories that you visited in the past, used to quickly navigate complex directory structures -- Python
• autoenv - Autoruns a .env file in a directory when you cd into the directory -- Python
• Awesome Shell - Massive collection of shell tools -- collection
• Babun - Pre-configured Cygwin with many more features and a better design -- various lang
• Bash-it - bash version of the oh-my-zsh shell environment -- various lang
• BashGuide - Targeted at beginners -- wiki
• Bash Hackers Wiki - Human-readable bash documentation so you don't have to dig through the man page -- wiki
• Bash Pitfalls - Common errors that bash programmers make -- wiki
• cheat - create and view interactive cheatsheets on the command-line -- Python
• comm - Display lines that two files have in common (eg: the opposite of diff) -- built-in
• CommandlineFu - Killer code snippets -- collection
• CRUSH (Custom Reporting Utilities for SHell) - Killer toolset for working on delimited data, by Google -- C
• Cygwin - GNU shell and tools for Windows -- C Windows
• dotfiles by Paul Miller - Beautiful and flexible Mac terminal configuration files and utilities, ZSH-based -- shell OS X hawt
• dotfiles - Unofficial guide to dotfiles on GitHub -- collection
• Environment Modules - Dynamic modification of your shell environment using modules -- Tcl Windows
• fzf - Command line fuzzy finder, supports tmux/bash/zsh -- Golang
• icdiff - diff tool that highlights the differences -- Python OS X
• moreutils - "Collection of the unix tools that nobody thought to write long ago when unix was young" -- neat
• notify - Send a notification from your Linux system to an Android app on your phone, good for long running shell commands -- JavaScript Android
• pigz - Parallel gzip for multi-processor/core systems -- C
• pv - Shows the progress of data as it flows through a pipe -- built-in
• ShellCheck - Checks shell scripts for common mistakes, essentially a linter / static analysis -- in-browser
• Shell Style Guide - By Google -- collection
• tldr - Simplified and community-driven man pages, cuts out a lot of cruft -- collection
• Unix Toolbox - A collection of Unix/Linux/BSD commands and tasks for advanced users -- collection

Software Development Tools

Build systems, stubs/mocks, CI/CD, cheat sheets, and other - see also Git Tools and Collaboration Tools and Editors and Shell Scripting and Tools and Web and HTTP Tools and Tracing and Profiling and Web and HTTP Performance Analysis Tools

• ack2 - grep-like tool designed to search source code -- perl
• afl-unicorn - Fuzz any piece of binary that can be emulated by Unicorn Engine -- C
• ag (aka The Silver Searcher) - Source code searching tool, a better grep -- C
• Bazel - Google's build system -- Java
• Buildbot - CI framework -- Python
• cwrap - Wrappers for creating test scenarios and faking behavior/ stubbing, mostly network focused, by the Samba guys -- C
• dev-setup - Automated setup scripts for laptop tools like Sublime Text, AWS, Spark, Android dev, and more -- collection
• drone - CI platform built on Docker / containers, can also deploy to Kubernetes -- Golang
• dropwizard - Simple library for building production-ready RESTful web services -- various lang
• Fossil - Simple all-in-one SCM -- various lang
• fswatch - Cross-platform for watching files and taking action when they change -- C++
• gdb TUI - Curses / menu-based interface for GDB, much easier than REPL mode -- C
• GoCI - Go continuous delivery platform by ThoughtWorks -- Java
• Guard - Flexible framework to take action on file system change event -- Ruby gem
• Gulp - Built system / toolkit that helps you automate time-consuming tasks in your development workflow -- JavaScript
• Jenkins - The most popular CI orchestration tool, supports a billion plugins -- various lang
• jenkins-job-dsl (Jenkins Job DSL Plugin) - Groovy-based DSL for writing Jenkins jobs -- Groovy
• Jenkins job-config-history Plugin - Tracks changes to system and job configurations -- Java
• Jenkins Job Builder - Takes simple descriptions of Jenkins jobs in YAML or JSON format and uses them to configure Jenkins -- Python pip
• Jenkins Log Recorder - Helps you group relevant logs together while filtering out the noise -- Java
• Jenkins Pipeline Mutlibranch Plugin - Automatically creates a new Jenkins job whenever a new branch is pushed to a source code repository -- Java
• Jenkins ThinBackup - Jenkins plugin that backups configurations (not workspaces or archives) -- Java
• JSON Server - Full fake REST API for quickly prototyping and mocking in 30 seconds -- JavaScript
• Meld - Diff tool, recommended -- Python
• MockServer - Web server to remotely or locally mock HTTP/HTTPS and similar -- Java
• mountebank - Stub downstream resources for testing, supports HTTP HTTPS SMTP TCP -- JavaScript Windows OS X
• Ninja - Small build system with a focus on speed -- Python
• PatchELF - Simple utility for modifying existing ELF executables and libraries -- C
• PEview - Easily and quickly view the structure and content of Windows EXE DDL LIB Portable Executable (PE) files -- closed source
• PRoot - chroot, mount --bind, and binfmt_misc without privilege/setup -- C
• Proxygen - Modern C++ HTTP library, by Facebook -- C++
• REST-assured - Java DSL for testing of REST services -- Java
• RocksDB - Library that provides an embeddable, persistent key-value store for fast storage - by Facebook -- C++
• SonarQube - Platform and dashboard for managing code quality -- Ruby Java
• Sonatype Nexus - Software / binary artifact storage -- Java
• SourceGraph - Perhaps the best code search and navigation engine -- Golang
• SymbolHound - Search engine that doesn't ignore special characters, great for programming questions -- try it
• watchman - Watch files and take action when they change (eg: kick off the CI system), by Facebook -- C
• WireMock - Flexible stubbing and mocking services -- Java

SSH Tools

Misc SSH stuff - see also Terminal Tools and SSH Clients for clients and Orchestration for parallel SSH tools and Shell Scripting and Tools

• autossh - Automatically restart SSH sessions that stop passing traffic -- C
• Corkscrew - Tunnel SSH through HTTP proxies -- C
• Dropbear - Small / minimal SSH client and server, often used in IoT and embedded devices -- C
• Keychain - Manage SSH and GPG keys, acts as a frontend to ssh-agent, only enter passphrase once per reboot -- shell
• Match - Creates a conditional block, great for controlling actions on a per-user and/or per-host basis in sshd_config -- built-in
• Mosh (Mobile Shell) - Remote shell that supports roaming (client IP address changes) and intermittent connectivity, by MIT -- C++
• Shuttle - A simple SSH shortcut menu for macOS -- Objective-C
• ssh-chat Instead of a shell you get a chat prompt -- Golang
• ssh-ldap-helper - Store public keys in LDAP -- built-in
• SSHFS - Mount remote file systems using a SSH tunnel -- built-in
• sshmuxd - SSH jumphost style proxy -- Golang
• sshttp - Port multiplexer that hides a SSH daesmon behind HTTP, HTTPS, or SMTP on a single port -- C
• SSH Guard - Think fail2ban for SSH -- C
• SSH Power Tool (sshpt) - Execute commands and upload files to many servers simultaneously via SSH without using pre-shared keys -- Python pip
• storm - CLI and GUI tool to manage your SSH connections (add, delete, list, search) -- OS X

SSL Tools

SSL, TLS, CAs, and similar tools for interacting with HTTPS and SSL certificates - see also Web and HTTP Tools and Security Tools

• BadSSL.com - Test various clients (browsers, etc) against bad SSL configs -- in-browser
• BoringSSL - Google's fork of OpenSSL, does not guarantee API and ABI compatibility -- C
• cfssl - PKI/TLS swiss army knife, has CLI and a HTTP API server for signing, verifying, and bundling TLS certificates -- Golang
• cipherscan - Find out which SSL ciphersuites are supported by a target -- Python
• Dogtag Certificate System - PKI component of FreeIPA, by Fedora -- C
• Fizz - C++14 implementation of the TLS-1.3 standard, by Facebook -- C++
• HSTS (HTTP Strict Transport Secuirity) - Forces browsers to interact with a site by only using HTTPS -- article
• HSTS Preload Submission - Submit your site to be preloaded in major browsers -- security
• Let's Encrypt - Free SSL certs from a real CA -- in-browser
• Mozilla Server Side TLS - Mozilla's extensive server side TLS configuration guide -- wiki
• Mozilla SSL Configuration Generator - Generate SSL configs for Apache, Nginx, ELB, HAproxy and more -- in-browser
• nogotofail - Spot and fix weak TLS/SSL connections and sensitive cleartext traffic, by Google -- Python
• Qualys SSL Server Test - Evaluates and provides recommendations for the SSL settings of any web site -- in-browser
• s2n - Amazon's implementation of the TLS/SSL protocols in C99 (simple, small, fast, secure) -- C
• Server Name Indication (SNI) - Think vhosts for SSL -- article
• sslconfig - CloudFlare's Internet facing SSL cipher configuration, patches for Nginx and OpenSSL -- C
• ssldump - The de-facto repo -- C
• SSLsplit - Transparent and scalable SSL/TLS interception -- C
• sslyze - Fast and full-featured SSL scanner, written in Python -- Python OS X
• stunnel - Create simple TLS tunnels for existing services (eg: telnet, nc, etc) -- C

Storage Tools

The storage junk drawer - see also Backups and Cloud File Sync and Sharing and Live CD Tools

• BeeGFS - Parallel cluster file system, worth examining -- C++
• CrystalDiskInfo - S.M.A.R.T. GUI tool for Windows -- closed source Windows
• FlashCache - General purpose, write-back block cache -- C
• fs-cache - Modern NFS client-side caching -- built-in
• Linux-IO Target (LIO) - Create and share iSCSI, Fibre Channel, FC over Ethernet, and other storage targets from Linux VMs -- built-in
• Linux Journal - Linux Swap Space - Superb article about Linux swap, includes some tuning parameters -- article
• lsblk - List block devices -- built-in
• ncdu - ncurses version of "du" -- built-in
• Parted Magic - Resize, grow, shrink, clone, recovery, wiping, benchmarking, and more. Supports Linux and Windows file systems -- Windows
• snapper - CLI tool to manage Btrfs snapshots, snapshot timelines, and more -- various lang
• System Storage Manager (SSM) - Generic CLI for managing all types of storage (DM, LVM, multipath), added in RHEL 7 -- built-in

Storage Performance Analysis Tools

Grind your disks into dust - see also Performance Analysis Tools and Tracing and Profiling

• Bonnie++ - The classic, still updated -- built-in
• Connectathon Test Suite - NFS stress testing and benchmarking tools -- various lang
• fio - Supports 19 different I/O engines (sync, mmap, libaio, posixaio, etc), very powerful -- C
• Fnotifystat - Dumps the file system activity in a given period of time -- C
• ioping - Monitor I/O latency in real time -- C
• iorate - Originally written by EMC, now open source -- C
• iotop - top for I/O requests, displays information on a per-process basis -- Python
• IOzone - Supports NFS, still being updated! -- C
• Threaded I/O Tester (tiobench) - Threaded I/O tester, tiotest and tiobench -- C

Terminal Tools and SSH Clients

Fancy SSH clients, terminal sharing, and similar tools - see also SSH Tools and Orchestration for parallel SSH tools and Shell Scripting and Tools

• Bitvise SSH Client - Feature-rich SSH & SFTP client for Windows, free for individual use -- closed source Windows
• Byobu - An enhanced version of the "screen" utility -- shell OS X
• ChromaTerm-- - Pipe stdin to this program which highlights based on user defined regexs in .conf file -- C
• ConnectBot - Open source SSH client for Android -- Java Android
• Guacamole - Clientless (in-browser) remote desktop gateway, supports VNC and RDP -- various lang
• i2cssh - csshX like ssh tool for iTerm2 -- Ruby
• iTerm2 - Killer terminal replacement for Mac -- OS X -- Objective-C
• KiTTY - PuTTY fork with additional features -- Windows
• MobaXterm - Tabbed SSH, VNC, and RDP client for Windows, free for personal use -- closed source Windows
• mRemoteNG - Open source, tabbed, multi-protocol, remote connections manager -- Windows
• MTPuTTY (Multi-Tabbed PuTTY) - Multiple PuTTY sessions in a single window -- Windows
• NoVNC - Client-less VNC in a web browser, uses HTML5 and WebSockets -- in-browser
• PuTTY - The classic SSH client -- Windows
• PuTTYtray - PuTTY in the systray + additional features -- C
• reptyr - Reparent a running program to a new terminal -- C
• screen - Detatch and re-attach to shell sessions while they continue to run in the background -- C
• SuperPutty - Allows the PuTTY SSH client to be opened in tabs -- Windows
• tmate - Instant terminal sharing, a tmux fork -- OS X
• tmux - Alternative to GNU screen, also used for terminal sharing -- C
• tmux Resurrect - Persists tmux environment across system restarts -- shell
• Warp - Securely share your terminal, like handing a co-worker your keyboard -- Golang
• WinSCP - The well-known SCP client -- C Windows
• x2go - One of the best remote-desktop-over-SSH clients -- Windows OS X
• Xshell - SSH client for Windows, free for personal use -- closed source Windows

Tracing and Profiling

OS kernel and process-level tracing and profiling tools - see also Performance Analysis Tools and Network Performance Analysis Tools and Web and HTTP Performance Analysis Tools and Metrics and Time Series Data and RDBMS Performance Analysis Tools

• bcc - Next generation, Linux 4.x kernel tracing tool suite, uses eBPF (Extended Berkeley Packet Filters) -- C
• eBPF - DTrace + SystemTap, requires 4.x kernel, mostly uses bcc -- various lang
• kdump - Linux kernel dump facility (where to save it, what to save, etc) -- C
• Linux Trace Toolkit - Next Generation (LLTng) - Linux kernel tracer and profiler, lower overhead than System Tap -- C
• ltrace Tutorial - ltrace (library call tracer) tutorial by Red Hat -- article
• lttng-analyses - Official collection of LLTNG scripts and snippets -- collection
• Mastif Visualizer - Visualizer for the Valgrind's Mastiff utility -- C++
• OpenSnoop - Continually monitor for file opens -- shell
• OProfile - System-wide statistical profiling tool -- C
• perf - User-land performance analysis tool, a sampling profiler -- C
• perf-tools - Uses perf and ftrace, includes iosnoop -- Brendan Gregg
• pstore - Save kernel crash info in a platform-specific persistent memory so data is not lost (eg: disks failed so write dump to NVRAM instead) -- article
• Record and Replay (rr) - Record the failure once, then debug the recording deterministically, supports C and C++, by Mozilla -- C C++
• strace - System call tracer for user space processes -- built-in
• SystemTap (stap) - Linux kernel tracing and performance analysis tool -- C C++
• Valgrind - Tool suite that includes cache profilers, heap profiles, thread race condition checkers, and more - a CPU-level emulator -- C

Two Factor Authentication

Universal 2nd Factor (U2F) is the successor to two-factor authentication / TFA / 2FA and multi-factor authentication / MFA. Avoid using SMS if possible - see also VPNs and Tunnels and Secrets Management

• Authelia - 2FA and SSO for your apps via Docker on Kubernetes, supports Yubikey, Google Authenticator, and e-mail based password reset -- Golang
• CentOS 7 2FA VPN - VPN with CentOS 7 + FreeRADIUS + FreeIPA + Google Authenticator -- tutorial
• FreeOTP - Open source fork of Google Authenticator, by Red Hat -- C mobile
• Google Authenticator - Official project, supports Android, iOS, and has a PAM module for SSH 2FA -- C
• Nitrokey - Open source thumb drive for authentication -- various lang
• One Time Password - PAM module allowing single-use passwords to login to a system -- C
• pam-u2f - PAM module for auth via U2F compatible devices, by YubiKey -- C
• privacyIDEA - All in one solution for two-factor authentication across all your organization's devices such as OTP tokens, SMS, VPNs, SSH keys, Windows, keyfob, etc -- various lang
• Titan Security Key - Physical key for FIDO 2FA, unphishable (really) -- physical
• W3C's Web Authentication - Standards driven, supports various tokens and OTP generators -- specification
• yubico-pam - PAM module for use with YubiKey devices -- C
• yubikey-full-disk-encryption - Encrypt storage on a LUKS partition using a Yubikey -- Shell
• YubiKey GPG & SSH Guide - Guide to using YubiKey as a SmartCard for GPG and SSH -- tutorial

Virtualization and SDN

OS, network, and storage virtualization, emulation, and simulation including SDN, load balancers, and firewalls - see also Containers for container-only network meshes and VMware Tools

• BlueStacks - Android emulator that you can run on Windows, run apps from the Play store, etc -- various lang
• BusyBox - Bootable Linux with tiny versions of many common UNIX utilities in a single small executable -- C
• Calico - L3 fabric that runs a vRouter on each node, supports containers -- Python
• DOSbox - Open source DOS emulator, great for running old games or utilities -- C C++
• Firecracker - Micro-VM for serverless computing, by Amazon -- Rust
• FreeNAS - BSD-based NAS, supports ZFS -- C
• GitHub Load Balancer Director - Layer 4 load balancer -- C
• GNS3 - Cisco and other network simulator that runs in VirtualBox or Qemu/KVM -- Python
• HAproxy - Open source software load balancer -- C
• haproxyctl - Wrapper to talk to the HAProxy socket, as well as regular init (start stop restart) shit -- Ruby gem
• Katran - A high performance layer 4 load balancer library, by Facebook -- C++
• KVM (Kernel Virtual Machine) - The one, the only -- C
• kvm-tools - CLI tools for managing qemu-kvm domains -- C
• KVM Management Tools - Great list of KVM management tools on the KVM wiki, updated frequently -- collection
• libvirt - Open source API, daemon and management tool, used with many virtualization solutions -- C
• Linux-IO Target (LIO) - Create and share iSCSI, Fibre Channel, FC over Ethernet, and other storage targets from Linux VMs -- built-in
• LVS (Linux Virtual Server) - Linux-based load balancer, also includes the IPVS kernel module -- C
• Mininet - Easily setup networks for testing on your laptop with VirutalBox -- various lang
• Minio - An open source object storage server compatible with Amazon S3 APIs -- Golang
• ns-3 - Network simulator, mostly focuses on wireless IP such as Wi-Fi, WiMAX, or LTE and routing protocols such as OLSR and AODV -- C
• Open vSwitch (OVS) - Production quality software switch -- C
• OpenFiler - Linux-based NAS, supports most protocols and storage types -- C
• Oracle VM VirtualBox - Easy, simple virtualization -- C C++ Windows OS X
• oVirt - Virtualization management platform, the upstream for Red Hat Enterprise Virtualization (RHEV) -- Java
• Packet Tracer - Cisco network simulator, by Cisco -- closed source Windows OS-X
• pfsense - The best firewall software, supports appliances and live CDs -- C
• phpVirtualBox - Web front-end for VirtualBox -- PHP
• QEMU (Quick EMUlator) - Also supports hardware emulation (SPARC, RISC, etc) -- C
• Seesaw - Load balancer based on Linux Virtual Server (LVS), by Google -- Golang
• Shadow - Network simulator that runs real applications like Tor and distributed systems of thousands of nodes on a single machine -- C
• Squid - Reverse proxy, caching server, web traffic filter, and more -- C++
• Traefik - Modern HTTP reverse proxy and load balancer, supports many backends -- Golang
• Unicorn Engine - CPU emulator framework (ARM, AArch64, M68K, Mips, Sparc, X86) via QEMU -- various lang
• virt-manager - KVM / Xen / LXC GUI -- Python
• WANem (Wide Area Network Emulator) - WAN emulator -- C
• WINE - Compatibility layer for running Windows apps on POSIX-compliant OSes -- C OS X
• Xen - It's a hypervisor! -- C
• XenServer - Successor to Xen Cloud Platform (XCP) -- C
• xhyve - Lightweight OS X virtualization based on bhyve -- C OS X
• ZeroTier - Cloud / provider-agnostic private network backplanes, network virtualization -- C++ all platforms

VMware Tools

Mostly unofficial VMware tools and scripts - see also Virtualization and SDN

• Compliance Checker for vSphere - Provides detailed compliance checks against vSphere hardening guidelines, official tool -- closed source
• FastSCP - Super fast SCP client for Windows for moving stuff around in a VMware environment (ISOs, VMDKs between data stores, etc) -- closed source
• Flings - Tons of very useful apps written by VMware engineers, worth exploring A++++ -- closed source? various lang
• Onyx - Do something in vSphere and it will create a PowerCLI script to do that thing that you just did -- closed source PowerShell Windows
• open-vm-tools - OSS alternative to VMware Guest Tools -- C
• PowerCLI - VMware's CLI -- closed source
• RVtools - Killer GUI for viewing information about your VMware environment -- closed source .NET Windows
• RVtools Export - Wrapper script to save daily snapshots of your environment using RVtools -- PowerShell
• Sexigraph - Graphite-based visualization appliance for Sexilog -- various lang
• Sexilog - ELK stack virtual appliance designed for vSphere / VMware ESXi logs -- various lang
• vCheck - Get an overview of a new environment or check the health of an existing one -- PowerShell
• vDisk Informer - Check vDisks alignment and see if they have wasted space -- closed source Windows
• vGhetto Script Repository - Various scripts from virtuallyGhetto -- various lang
• VMware Community PowerPack - A variety of scripts from Virtu-al.net and now other blogs such as ict-freak.nl and ntpro.nl -- lost-to-the-internet PowerShell
• VMware on Github - VMware's Github repos -- various lang
• VMware Sample Exchange - Code samples & scripts by both VMware and the community -- various lang
• vSphere Health Check Report - Reports a massive amount of information, run it on a schedule -- closed source perl
• vSphere Mobile Watchlist - Monitor VMs on your phone -- closed source mobile

VPNs and Tunnels

VPN client & servers, tunneling proxies, DNS tunneling, simple host-to-host tunnels, and related tools - see also SSL Tools and SSH Tools and Virtualization and SDN

• Algo VPN - IKEv2 Ubuntu-based strongSwan VPN server deployed to any cloud via Ansible -- Python
• AutoVPN - Spin up and autoconfigure OpenVPN instances in AWS -- Python
• BrowserLeaks - See if info is leaking from your browser (your real IP when you're behind a VPN, etc) -- in-browser
• CentOS 7 2FA VPN - VPN with CentOS 7 + FreeRADIUS + SSSD + Google Authenticator -- stepbystep
• Corkscrew - Tunnel SSH through HTTP proxies -- C
• DNS Leak Test - See if DNS queries are leaking outside of your VPN / secured network -- in-browser
• dnscrypt-proxy - DNS proxy, with support for modern encrypted DNS protocols such as DNSCrypt v2 and DNS-over-HTTP/2 -- Golang
• dnscrypt-wrapper - Add dnscrypt support to any resolver, server-side dnscrypt proxy -- C
• fwknop (FireWall KNock OPerator) - Single Packet Authorization (SPA), authoriation packet from you opens firewall rules so only you can get in -- various lang
• IP Leak - Test to see if your browser is leaking information -- in-browser
• kcptun - Secure and fast tunnel based on KCP, can increase throughput -- Golang
• localtunnel - Share a HTTP/web service on your local development machine without messing with DNS and firewall settings -- JavaScript Windows OS X
• MACsec aka 802.1AE - Use me for confidentiality and integrity at layer 2, useful for WAN links -- standard
• Magic Wormhole - Safely and simply send arbitrary-sized files and directories (or short pieces of text) from one computer to another -- Python
• n2n - L2 over L3 VPN that uses a peer-to-peer architecture -- C
• nipe - A script to make Tor Network your default gateway -- perl BOOYA
• OpenConnect - Supports Cisco's AnyConnect SSL VPN -- C
• OpenVPN - The one and only -- C
• Pritunl - Distributed enterprise VPN server built using the OpenVPN protocol, supports Google sign-in -- Python
• Shadowsocks - A secure socks5 proxy, designed to protect your Internet traffic -- various lang most platforms
• SoftEther - Perhaps the best VPN software out there -- C
• spiped - Create encrypted pipes between socket addresses using pre-shared keys (PSKs), similar to ssh -L -- C
• sshttp - Port multiplexer that hides a SSH daemon behind HTTP, HTTPS, or SMTP on a single port -- C
• sshuttle - Transparent proxy server / VPN, doesn't need admin, forwards over SSH, supports DNS tunneling -- Python OS X
• SSH Through or Over Proxy - How to create a HTTP(s) tunnel for your SSH traffic -- article
• Streisand - Set up a server running a wide variety of privacy software, so easy that grandma can use it, Ansible-based -- Python
• strongSwan - IPsec-based -- C
• stunnel - Create simple TLS tunnels for existing services (eg: telnet, nc, etc) -- C
• tinc - Simple, multi-platform VPN -- C
• WireGuard - Performant in-kernel VPN server with DJB Crypto and very modern primitives -- C
• Ubuntu IKEv2 VPN Setup - Simple script that sets up a IKEv2 VPN with strongSwan on Ubuntu -- shell

Web and HTTP Tools

RPC is dead, long live RPC - see also SSL Tools and Networking Tools

• API Blueprint - Supports bindings/plugins for many APIs -- various lang
• Caddy - Web server with automatic TLS and more -- Golang
• Fiddler - HTTP/HTTPS debugging proxy for any browser, system or platform -- closed source
• gRPC - High performance RPC via HTTP/2, by Google -- C
• h2i - Go's interactive HTTP/2 console debugger, send raw frames, etc -- Golang
• Hamms - Simulate/create connection failures, malformed response data, slow servers, fat headers, and more! -- Python
• htaccess Snippits - Huge collection of common and useful .htaccess snippets, please contribute -- collection
• http-traceroute - Shows the entire route including cookies, redirects, and response codes -- Ruby
• httpdiff - Perform the same reuqest against two HTTP servers and diff the results -- Golang
• httpie - curl replacement with many new features -- Python
• httptoolkit - Open-source HTTP(S) debugging proxy, analyzer & client -- Typescript
• htty - A console application for interacting with web servers -- Ruby gem
• Huginn - Build agents that perform automated tasks/workflows for you online or locally, like IFTTT -- Ruby
• Insomnia REST Client - An alternative to POSTman, additional features -- Electron Windows OS X Linux
• JSON Server - Full fake REST API for quickly prototyping and mocking in 30 seconds -- JavaScript
• jq - Command line JSON processor and manipulator -- C
• localtunnel - Share a HTTP/web service on your local development machine without messing with DNS and firewall settings -- JavaScript Windows OS X
• mitmproxy - Intercept, modify, replay and save HTTP/S traffic - even edit flows on the fly -- Python pip
• mountebank - Stub downstream resources for testing, supports HTTP HTTPS SMTP TCP -- JavaScript Windows OS X
• Newman - CLI companion for Postman -- JavaScript
• nghttp - CLI HTTP/2 client, similar to curl/wget and more -- C
• nginxconfig - Web-based nginx config generator -- in-browser
• ngrok - Reverse proxy that creates a secure tunnel from a public endpoint to a locally running web service and captures & analyzes all traffic over the tunnel for later inspection and replay -- rocks Golang
• OpenResty - Turn nginx into a non-blocking API server -- C
• PageKite - Makes HTTP servers or SSH publicly available on any server -- Python
• POSTman - Create and share API and HTTP requests, great for testing and sharing -- Chrome
• Puppeteer - Provides a high-level API to control headless Chrome over the DevTools Protocol -- JavaScript
• Pushpin - Proxy server that adds WebSockets to existing request-response APIs -- C++
• react-admin - Add an React admin GUI to any RESTful API -- JavaScript
• Redirect Detective - See the complete path a redirected URL goes through -- in-browser
• Repose - REST proxy, solutions to API tasks such as auth, rate limiting, API validation, HTTP logging, and much more -- Java
• Resty - CLI REST client you can use in shell/bash/zsh pipes -- shell
• SecurityHeaders.io - Scan your web site's HTTP headers -- in-browser
• Swagger - Popular API development library, now the OpenAPI standard -- various lang
• tengine - A distribution of Nginx with some advanced features, by Alibaba -- C
• tortilla - Easily wrap web APIs -- Python pip
• Tyk - API gateway -- Golang
• urlscan.io - Displays tons of stats and info about any given URL -- in-browser
• Varnish - Caching HTTP accelerator -- C
• vcr - Record and play back HTTP sessions -- Ruby gem
• webhook - Super simple webhook server -- Golang
• wuzz - Interactive cli tool for HTTP inspection (menu-based) -- Golang

Web and HTTP Performance Analysis Tools

Load generation, debugging, benchmarking, and profiling for SaaS, webapps, and HTTP(S) - see also Performance Analysis Tools and Network Performance Analysis Tools

• Awesome Web Performance Optimization - Collection of web performance optimization (WPO) tools, articles, and more -- collection
• Betwixt - Web debugging proxy with a Chrome DevTools look -- JavaScript
• Brotli - Modern alternative to gzip, better packing, performs well with HTTP/2, HTTPS only -- zoooooom
• django-debug-toolbar - Panels that display profiling information about the current request/response -- Python pip
• Chrome DevTools - Many built-in tools for performance analysis -- mostly OSS
• Gatling - HTTP, JMS, and WebSocket load generator -- Scala
• Google Web Tracer - Helps you identify and fix performance problems in your web applications, by Google -- Chrome
• Firefox Developer Tools - A full list of built-in Firefox developer tools including performance tools -- various lang
• h2load - HTTP/2 and SPDY load generation tool, part of the nghttp2 suite -- C
• HAR Analyzer - HTTP Archive analyzier for troubleshooting from a browser perspective, by Google -- in-browser
• httping - Simple program that "pings" a URL and shows response time -- C
• Jaeger - OpenTracing compatible distributed tracing system, works well with Istio and Envoy, by Uber -- Golang
• JMeter - Designed to load test functional behavior and measure performance, written in Java -- Java
• Locust - Load generation tool written in Python that allows you to define user behavior -- Python
• ngxtop - Real time top for nginx -- Python
• OpenTelemetry - Vendor-neutral distributed tracing -- various lang
• OpenZipkin - Distributed tracing systems for SaaS and webapps, by Twitter, based on Google's Dapper -- Scala
• Packetbeat - Distributed packet monitoring system that can be used for application performance management -- Golang
• PageSpeed Insights - Analyzes the content of a web page, then generates suggestions to make that page faster, by Google -- in-browser
• PageSpeed Module - Open-source server modules that optimize your site automatically (nginx and Apache), by Google -- various lang
• peep - Heap inspector for live memcached instances -- Ruby
• redis-faina - Query analyzer that parses Redis' MONITOR command for counter/timing stats about query patterns, by Facebook -- Python
• Tsung - Distributed stress tester, also supports stress testing DBs -- Erlang
• Web Page Test - Free website speed test from multiple locations around the globe using real browsers (IE and Chrome) and at real consumer connection speeds -- in-browser
• wrk - Multi-threaded CLI-based HTTP load generation tool -- C
• wrk2 - Fork of wrk that fixes the "coordinated omissions problem" -- C
• UpTrends Uptime Checker - Check a URL's response time from ~30 different sites around the globe -- in-browser
• Varnish Dashboard - Realtime dashboard for Varnish cache servers -- JavaScript

Misc Tools of Note

Everything else

• Adblock Radio - An adblocker for live radio streams and podcasts -- various lang
• Anti-Ablock Killer - Keep your ad-blocker active when pages take anti-blocking measures, requires Greasemonkey or similar -- JavaScript
• AppLock - Lock individual apps on Android -- Java
• Architecture Decision Record - Document that captures an important architectural decision made along with its context and consequences -- template
• AutoIT - Scriptable GUI input for Windows (think AutoHotKey) but with a BASIC-like syntax -- closed source
• Bypass Paywalls - Shhh -- Firefox Chrome
• Cloud Custodian - Rules engine for managing public cloud accounts and resources via policies, by Capital One -- various lang
• conserver - Virtual console server with many features (multi-user, console log history, etc) -- C
• Cookie Autodelete - Browser add-on that's essentially a cookie whitelist / grey list -- Firefox Chrome
• CRIU (Checkpoint Restore in Userspace) - Freeze a process, save it to disk, then resume it later -- insane
• crumbs - Simple mind maps with asterisks - great for brain dumping with little transcription overhead -- Golang
• Domain Block List - The only Pi Hole blocklist you'll need -- collection
• Etcher - SD card writing software, easy -- various lang
• f.lux - Changes your screen from blue light to yellow light when the sun sets to tell your brain it's night time -- closed source OS X Windows
• FigmaToCode - Outputs Figma objects to Tailwind, Flutter, or SwiftUI code -- JavaScript
• Firefox Multi-Account Containers - Cookies are separated by container, allowing you to use the web with multiple identities or accounts simultaneously -- Firefox
• Fossor - Automate on-call investigation steps, by LinkedIn -- Python pip
• Geocities-izer - Make any HTML web page look like a Geocities page -- sweeeeeeet
• googler - Google search, news, and site search from the terminal, slick -- Python
• Google Advanced Operators for Web Search - Search modifiers for more accurate results, by Google -- collection
• GoodRX - Coupons for prescriptions, vaccines, and more, can be used pre-deductible, USA-centric -- ez savings
• gosu - Simple Go-based setuid+setgid+setgroups+exec for stepping down privs, use me to avoid weird su and sudo TTY bugs -- Golang
• Highlight This - Multi-highlight, regex, all data local, tons of features -- Chrome
• Homomorphic Encryption - Allows data to be encrypted and out-sourced to 3rd parties for processing, all while encrypted (or remove HIPAA barriers) -- article
• HTTPS Everywhere - Uses client-side tricks to force misconfigured sites to use HTTPS all the time, by the EFF (donate) -- Firefox Chrome
• Huginn - Build agents that perform automated tasks/workflows for you online or locally, like IFTTT -- Ruby
• ICANN Domain Lookup - Use this when searching for a domain to buy because they cannot use your searches to jack up the price -- in-browser
• inxi - "a full featured system information script" (hardware info, etc) -- shell
• IPTV - Collection of 8000+ publicly available IPTV channels from all over the world -- screw off Bundesliga -- collection
• Library Extension - Browser extension that shows you which Amazon books are available free at your local libraries, please donate -- closed source
• Locast - Watch your local broadcast TV for free on any device, USA geo-locked, please donate -- all platforms!
• Mail Tester - Test the spammyness of your e-mails -- in-browser
• maybe - Allows a dry run of almost any Linux binary, see the files it will modify, calls made, etc -- Python pip
• Maza - Like Pi-hole but local and using your operating system -- shell
• Mjolnir - Automation for OS X, think AutoHotKey for Mac -- C OS X
• MultiRBL - SMTP blackhole lookup tools -- in-browser
• MX Toolbox - SMTP blacklist lookup, header analysis, and more -- in-browser
• Network UPS Tools (NUT) - Manage power devices from over 100 manufacturers using a single web interface -- C Windows
• NoRoot Firewall - Android app that logs connections to show overly chatty background apps and more -- closed source
• NoScript - JavaScript, XSS, tracker, Flash blockers and more - your condom for the Internet -- Firefox
• oauth2_proxy - A reverse proxy that provides authentication with Google, Github or other provider -- Golang
• Omni Calculator - 1500+ free calculators -- collection
• oomd - Userspace OOM killer, highly configurable and much improved over the kernel's built in OOM killer -- C++
• Open19 - Open data center hardware for standard size racks -- neat
• OpenBMC - Framework to build a complete Linux image for a Board Management Controller (BMC), by Facebook -- C
• PeerTube - P2P version of YouTube, don't let your videos get taken down, now supports live streaming -- free as in freedom
• Pi-Hole - Ad and tracking blackhole that covers your entire network with a single device -- hardware
• PineTime - An open source smartwatch -- hardware
• Privacy Badger - The best in-browser privacy and anti-tracking tool, by the EFF (donate) -- Chrome Firefox
• PrivacyTools.io - All in one collection, web site source is on GitHub -- collection
• Puffer - Re-transmits free over-the-air broadcast television signals received by an antenna located on the campus of Stanford University, USA geo-locked, by Stanford Platform Lab and many others -- in-browser Android
• repl.it - In-browser REPLs for a ton of languages -- in-browser
• RISC-V - The open source CPU that can run at >5Ghz while using 1/100th the power of a Xeon E7 -- hardware
• runwhen - Utilities for running commands at particular times, cron on steroids -- C
• Say What - Using speech-to-text to fully check out during conference calls -- Python
• scrcpy - Remote display and control of Android devices connected on USB or TCP/IP -- C
• Spectacle - Control desktop windows via keyboard shortcuts -- Objective C
• StackStorm - IFTTT for Ops -- Python
• Steps Recorder (aka Problem Steps Recorder) - Windows 7+, user records themselves reproducing a problem, they send video to you, you playback -- closed source
• Twilight - F.lux for Android -- closed source
• uBlock Origin - Ad blocker, only use Origin, do not use another uBlock -- Firefox Chrome
• unPaywall - When you view a paywalled scholarly article, Unpaywall automatically checks its open database of 28 million legal, open-access articles and tells you if you can get it elsewhere for free -- JavaScript
• WhosHere - Monitor an area for WiFi and Bluetooth probe requests to see when people (devices) come and go, with web UI and IFTTT webhook integraiton for Slack/SMS pushes -- PHP

Learning Resources

Free learning resources and collections of note (DevOps/SRE, cloud, information security, Kubernetes, Docker/containers, Python, Golang)

• 4+1 architectural view model - View model used for describing the architecture of software-intensive systems, based on the use of multiple, concurrent views (logical, physical, development, process) -- article
• A Gentle Introduction to Kubernetes - With more than just the basics -- tutorial
• A giant list of Google Cloud resources - From Google -- collection
• A Practical Guide to (Correctly) Troubleshooting with Traceroute - Presentation, really digs in -- article
• A Practical Introduction to Container Terminology - Concise breakdown, by Red Hat -- article
• A Visual Guide to Troubleshooting Kubernetes Deployments - With flowcharts -- handy
• Algorithms, 4th Edition - 100% free high quality ebook from Princeton -- book
• Amazon Builder's Library - Amazon shares their learnings -- articles
• An Illustrated Guide to Kubernetes Networking - See title -- article
• An Introduction to Distributed Systems - by Aphyr -- tutorial
• Ansible Examples - Shows features and how they work together, a great hands-on, official -- tutorial
• Ansible for DevOps - The recommended book to learn Ansible -- book
• Ansible Interactive Tutorial - Interactive tutorials for Ansible via Docker, super simple -- tutorial
• Ansible Automation Platform Workshops - Workshops, training decks, and guides, by Red Hat -- tutorials
• Application Layer Transport Security - Use mutual TLS to secure RPC calls between entities, designed with containers and microservices in mind -- article
• Architecture of Open Source Applications - The authors of four dozen open source applications explain how their software is structured, and why -- collection
• Archive.org aka The Internet Archive aka The Wayback Machine - Yo donate, this is beyond important -- the biggest collection
• Automate the Boring Stuff with Python - Exceptional -- book
• Awesome - Top level list of awesome lists -- collection
• Awesome AWS Workshops - Dozens of free interactive AWS workshops covering almost every major service (unofficial) -- tutorial
• AutoHotKey - Automate input (desktop and web forms, data entry, keybinds, etc) -- C++ Windows
• Awesome AutoHotKey - A collection of AutoHotKey scripts and libraries -- various lang
• Awesome System Design - System Designing articles, videos and resources for distributed computing -- collection
• AWS Breaking Changes - List of changes announced for AWS that may break existing code -- collection
• AWS CLI Cheat Sheet - See name -- tutorial
• AWS Security Maturity Roadmap - A series or actionable steps to improve the security of their AWS environments, updated annually -- collection
• AWS Stash - A collection of AWS related videos, podcasts, code repositories, whitepapers, and feature releases, all in a single, easy to search interface -- collection
• AWS Video Catalog - All official AWS videos cataloged and categorized (by topic, by year, etc) -- collection
• AWS Well Architected Labs - Hands on training and labs -- collection
• AWS Workshops - The official list of 100+ free AWS workshops -- collection
• Azure DevOps Labs - Self-paced -- training
• Bandit - A "wargame" that teaches the user how to use Linux -- neat
• BBR NKOTB - Excellent article that explains BBR and compares it to traditional TCP congestion and loss algorithms -- article
• Beyond the 12 Factor App - Free ebook, by Pivotal -- book
• blktrace how-to - mount -t debugfs debugfs /sys/kernel/debug && blktrace -d /dev/md2 -o - | blkparse -i - -- article
• Bookshop.org - Bookshop is an online bookstore with a mission to financially support local, independent bookstores - ditch Amazon! -- check it
• Borg, Omega, and Kubernetes - Lessons Learned from 3 Container Management Systems Over a Decade - Paper by Google -- article
• Building Secure & Reliable Systems - The third SRE book from Google, free -- book
• C4 Model - A modern approach for visualising software architecture -- article
• Chaos Engineering - Building confidence in system behavior through experiments, free book by Netflix -- book
• Cloud Design Patterns - Useful for building reliable, scalable, secure applications in the cloud, by Microsoft -- collection
• Cloud Native DevOps with Kubernetes - Full book -- book
• Cloud Native Landscape - A map that attempts to categorize most of the projects and product offerings in the cloud native space -- collection
• Command Line Text Processing - awk grep sed etc - interactive tutorial for newbies -- tutorial
• Common Python Mistakes - Link and discussion on HN -- article
• Comprehensive Python Cheatsheet - Includes many modules -- collection
• Computer Science Flash Cards - As described, can be converted into an Anki deck -- Python
• Container Training - Self paced and interactive, formerly Intro to Docker -- training
• Cool Store - An exercise to wire up small microservices into a larger application -- tutorial
• curl Exercises - Exercises for the 'curl' command -- tutorial
• Cybersecurity Canon - A Rock & Roll Hall of Fame for cybersecurity books -- collection
• Databases by Daniel Soper - From the ground up, personally recommended -- tutorial
• Design Patterns for Humans - An ultra-simplified explanation of repeatable software design patterns -- article
• Design Patterns - Wonderful collection of software development design patterns with examples, includes anti-patterns and refactoring guidelines -- collection
• Designing Data Intensive Applications - Book Notes - The one you need -- book
• DevDocs - Documentation browser for almost every API -- collection
• Devhints - Rico's dev & ops cheat sheets, nice little collection -- collection
• DevOps Conferences - Add and remove via PR, please contribute -- collection
• Discount for Student Dev - Programming and DevOps related discounts for .edu addresses, updated frequently, please contribute -- collection
• Docker Curriculum - One-stop shop for getting your hands dirty with Docker -- tutorial
• Dog vs. Cat: Docker Swarm Stacks - Examples for building full Swarm-based clusters including proxies, centralized logging, persistent storage, deployment pipelines, and more -- tutorial
• Easy-Python - Collection of Python resources that "you didn't know you would need" -- collection
• Effective Engineer - Notes from the book The Effective Engineer -- book
• Every Programmer Should Know... - A collection of (mostly) technical things every software developer should know -- collection
• Everything You Should Know About Certificates and PKI - Easy to understand tutorial -- tutorial
• Explain Shell - Enter a command-line to see the help text that matches each argument -- in-browser
• GKE Demo - Demonstration of complete, fully-featured CI/CD and cloud automation for microservices, done with GCP/GKE -- various lang
• GlossaryTech - Browser addon to learn tech terms with easy to understand defintions -- JavaScript
• go-perfbook - Outlines best practices for writing high-performance Go code -- article
• Goalkicker - Free programming ebooks -- collection
• Go by Example - Hands-on introduction to Go using annotated example programs -- tutorial
• Go Tooling In Action - A workshop covering all the tools used in the day to day life of a Golang dev -- tutorial
• Good Sleep, Good Learning, Good Life - Compiled knowledege about sleep with sources and citations -- zzz
• Google Cloud Solutions Architecture Reference - Some simple reference architectures -- collection
• Google's Technical Development Guide - Hands on, free, self-paced courses to help you develop your programming skills -- collection
• Hashicorp Learn - Official training for Vault, Consul, Terraform, Vagrant, Packer, and Nomad -- training
• HEAD - A free guide to HTML5 elements -- collection
• High Performance Browser Networking - What every web developer needs to know about the various types of networks (WiFi, 3G/4G), transport protocols (UDP, TCP, and TLS), application protocols (HTTP/1.1, HTTP/2), and APIs available in the browser (XHR, WebSocket, WebRTC, and more) -- book
• Hoopla - Digital movies, music and ebooks for USA public library members -- explore yours today
• How Complex Systems Fail - Paper by MIT, a great read for operations -- article
• How to Ask Good Questions - By Julia Evans -- article
• HTTP/3 Explained - QUIC = next generation TCP via UDP to bypass TCP's bad algos, used in HTTPv3 by haxx -- book
• In Defense of Swap - Well informed article about why you need some swap -- article
• Interactive Coding Challenges - 120+ interactive Python coding interview challenges (algorithms and data structures), includes Anki flashcards -- Python
• Interlibrary Loan - If your local library doesn't have a book or DVD in their collection they can use this service to order it from another library so you can borrow it out -- i'm learnding
• Introduction to Cloud Infrastructure Technologies - Notes from the superb course on edX -- collection
• Introduction to Kubernetes - Notes from the Introduction to Kubernetes course on edX -- collection
• Introduction to Linux - Endorsed by Linus himself, via edX -- course
• JavaScript Algorithms and Data Structures - JavaScript based examples of many popular algorithms and data structures -- JavaScript
• JVM Internals - A superb explanation of how the Java JVM works in easy to understand terms -- collection
• Kanopy - Streaming movies for USA public library members -- explore yours today
• Katacoda - In-browser labs and exercises with modern DevOps tools -- way cool
• Kubernetes Academy - k8s and containers tutorials as well as k8s certification preparation, by VMware -- tutorial
• Kubernetes and Service Mesh Workshop - 100% local, no need for cloud or additional hardware -- tutorial
• Kubernetes by Example - By the RedHat OpenShift team -- tutorial
• Kubernetes Clusters for the Hobbyist - How to securely run Kubernetes on providers that don't have ELBs, private networking, or persistent distributed storage (Hetzner Cloud, DigitalOcean or Scaleway) -- guide
• Kubernetes Failure Stories - Post mortems of Kubernetes outages, great way to learn -- collection
• Kubernetes Patterns - Free ebook from Red Hat and O-Reilly -- book
• Kubernetes Production Best Practices - Checklist -- collection
• Kubernetes the Hard Way - Build Kubernetes from the ground up as a learning exercise, uses Google Cloud -- tutorial
• Kubernetes the Hard Way Azure - Ported to Azure -- tutorial
• Kubernetes the Hard Way Vagrant - A port of Kelsey Hightower's "Kubernetes the Hard Way" tutorial to Vagrant -- tutorial
• Kubernetes the Hard Way VirtualBox - Bootstrap Kubernetes the hard way on VirtualBox. No scripts. -- tutorial
• Latency: A Primer - Web-app centric, defines all the terms you need to know then puts the knowledge together -- article
• LearnXinYMinutes - Super fast tutorials for almost every programming language -- collection
• Libby - App for ebooks and audio books for USA public library members, from OverDrive -- explore yours today Android iOS Windows 10
• Library Extension - Browser extension that shows you which Amazon books are available free at your local libraries, please donate -- closed source
• Linux Journey - ELI5 Linux training -- tutorial
• Linux Network Performance Parameters - Tutorial, data flows, explinations and more -- tutorial
• Linux Performance - Centralized page for all of Brendan Gregg's Linux performance material (slides videos pages etc) -- the man
• Linux Tracing Workshop - Hands on exercises with perf, bcc, and similar tools -- various lang
• Little Book of Python Anti-Patterns - See title -- book
• Memory Management Reference - All in one reference for memory management and garbage collection -- collection
• Microservices Design Patterns - A great foundation -- collection
• MIT OpenCourseWare - MIT's real course materials from 2400+ courses -- collection
• MySQL Performance Tuning Checklist - No bullshit list in about 15 bullet points -- collection
• Networking Cheat Sheets - Protocols, devices, ports, physical connectors, and more, by PacketLife -- collection
• Open Guides: AWS - Excellent summary of almost all services -- collection
• Open Source Society University (OSSU) - A complete education in computer science using free online materials -- collection
• OpenLibrary.org - From the good folks at Archive.org -- collection
• OpenShift Interactive Learning Portal - Learn OpenShift in your web browser, by Red Hat -- tutorial
• OpenShift v4 Demo - Give it a try -- tutorial
• OpenShift v4 Training - Official, requires AWS -- tutorial
• OpenShift v4 Workshop - By Red Hat -- tutorial
• OpenVim - In-browser vim tutorial -- tutorial in-browser
• Open Security Training - In the spirit of OpenCourseWare and the Khan Academy -- tutorial
• Open Source Intelligence Techniques - By the folks who wrote Buscador Investigative Operating System -- book
• Operating Systems: Three Easy Pieces - Probably the best OS book out there, free -- book
• Outages.org Mailing List - Report and discuss major outages, network status updates, etc -- mailing list
• OverAPI - Large collection of cheat sheets for almost anything -- collection
• OverDrive - Ebooks and audio books for USA public library members -- explore yours today
• OWASP Secure Coding Practices - Quick Reference Guide -- Great cheat sheet, language-agnostic -- collection
• Play with Docker - Docker playground that allows users to run Docker commands in a matter of seconds (Alpine + Docker in Docker (DIN)) -- learning
• Play with Docker Classroom - Interactive tutorials using Play with Docker (see above) -- learning
• Play with Kubernetes - A simple, interactive and fun playground to learn Kubernetes in your browser, by Docker -- in-browser
• Preparing a Google Kubernetes Engine Environment for Production - The best GKE summary, covers everything -- collection
• Production Readiness Checklist - Excellent checklist for pre-go-live, AWS-centric but great general advice -- collection
• python-patterns - A collection of design patterns and idioms in Python -- collection
• Python Cheat Sheet - Mostly based on the book written by Al Sweigart, Automate the Boring Stuff with Python -- collection
• Python Reference - A collection of useful scripts, tutorials, and other Python-related things -- collection
• PyVideo - Thousands of videos from hundreds of Python events and conferences, categorized by subject -- collection
• SaaS CTO Security Checklist - Categorizes and prioritizes actions by funding round -- collection
• Safari Books Online - ACM members get a full year of access for $99 ($19 for students) buy a membership here -- collection
• Scrum Guide - Explains Scrum in a concise and straightforward way in about 10 pages, by the creators -- article
• Secure Messaging Apps - True comparison of the technical features and merits of various apps, which are TRULY secure? -- collection
• Security 101 for SaaS Startups - Excellent checklist and guide in easy to understand terms for non-infrastructure people -- collection
• Security Engineering 3rd Edition - Free concise ebook, updated 2020 -- book
• Security Overview of AWS Lambda - From AWS -- article
• Site Reliability Engineering (SRE) by Google - Full, free, online version of the O'Reilly book -- the best
• Site Reliability Workbook - Free, by Google -- book
• Software Engineering at Google - Notes from the book, by me -- notes
• System Architecture - Great refresher, not so great for first time learners -- collection
• System Design Primer - Learn how to design large-scale systems -- article
• SymbolHound - Search engine that doesn't ignore special characters, great for programming questions -- try it
• Teach Yourself Computer Science - 9 subjects, they choose the best free source to learn each subject and explain why that source is the best - they did the research for you -- collection
• Tech Interview Handbook - SWE / dev-centric -- tutorial
• Technical Writing by Google - Technical writing, training by Google -- tutorial
• The Art of Command Line - The BEST interactive Linux tutorial, newbie focused -- learn it
• The Early Security Engineer’s First 90 Days Checklist - Aims to help security engineers and CISOs in early stage companies to prioritize their efforts in the first months of their new job -- list
• The Illustrated TLS Connection - Every byte of a TLS connection explained and reproduced -- article
• The Little Go Book - Free book, available in various formats - book
• The Manager's Path - Concise notes from the book -- notes
• Tiny Python Notebook - One of the best syntax cheat sheets -- article
• Twelve-Factor App - Language-independent rules for codebase, dependencies, build/release/run, dev and prod, logs, etc for a cloud/web-centric app -- collection
• Two Factor Auth (2FA) - Web sites that do and don't support 2FA, organized by category, submit PRs for changes -- collection
• Understanding OAuth2 and OpenID Connect - THE BEST article -- article
• Unix Rosetta Stone - The one and only resource for a mixed Linux/Unix environment -- translator
• USE Method - Brendan Gregg's rosetta stone for performance analysis and tuning -- article
• Use the Index, Luke - SQL indexing and tuning for developers -- collection
• Vim Adventures - A game to learn vi / vim using your browser -- in-browser tutorial
• Web Security Academy - Free online training for the creators of Burp Suite -- tutorial
• Weird Behaviors in S3 Bucket Policies - Documented weirdness of S3 buckets -- collection
• What Happens When... Kubernetes Edition - Walks through what happens behind the scenes when you do a kubectl run -- tutorial