Haskell

Haskell is a purely functional language with inferred static types and lazy evaluation. Functions, algebraic data types and pattern matching help you describe transformations and model valid states. Effects such as reading files are represented explicitly in types. These tools can prevent particular classes of mistakes; testing and careful design still matter.

Start learning Haskell

1. Install the tools. GHCup provides an entry point to the compiler and development tools.
2. Run a first program. Follow GHCup's First steps to compile a program, explore expressions in GHCi and create a Cabal project.
3. Make it useful. Build a small command-line tool that reads and transforms a text file. FP Complete's learning collection includes material on command-line options, JSON, HTTP and testing when you need the next piece.

Explore Haskell in practice

Browse Haskell projects, starting with Pandoc, or investigate organizations using Haskell and current job listings. For questions and examples from other developers, visit Haskell Discourse.

Mercury: learning Haskell for backend work

In a 2022 interview, Mercury CTO Max Tagher describes choosing Haskell for backend development and using types to prevent particular mistakes. He also discusses trade-offs around libraries, development speed and hiring.

Mercury's March 2026 account of its engineering training explains how new hires learn through exercises, daily mentoring and work tied to the company's backend. The program covers types, GHCi, testing, JSON handlers and database access. Its two-week format is supported by mentors and a specific codebase; it is an account of that onboarding process.

Explore Mercury on Beyond Tabs for company information and available roles.