mafia

Provides protection against cabal swindling, robbing, injuring or sabotaging people with chopsticks.

Overview

Mafia is a light weight but opinionated wrapper around Cabal that makes working on Haskell projects fun and easy.

The central idea is that upon cloning a project, you should only have to run mafia build to get up and running for development. This will pull down any git submodules, create a cabal sandbox, install dependencies and then build everything, tests and benchmarks included.

Cabal packages in the same git repository, or in git submodules, are discovered automatically and made available as source dependencies. This is particularly useful if you have many internal dependencies that are not published to Hackage. It allows for development of a package and its dependencies all at once, without having to publish intermediate builds of libraries and without having to resort to a monorepo.

All dependencies are cached globally in $HOME/.mafia/packages using a nix-like hashing system so that for a given set of transitive dependencies, a package is only ever built once. Source dependencies are also cached, using their dependencies and source code as the hash. This is critical for Haskell development at scale. At Ambiata we have around 150 Haskell packages which are being developed at a rapid pace, so it's crucial that we don't need to think about curating blessed sets of packages that we can cache as a single snapshot.

• Using Mafia For Your Own Projects.
• Mafia Command Reference.

System configuration

Mafia expects both GHC and Cabal to be installed and on the PATH.

Follow the guides below to configure your system correctly:

• Installing GHC
• Installing Cabal