haskell-flake is an ergonomic Nix module for Haskell development that makes things simpler. It works with plain Nix (no flakes), Nix flakes, or as a flake-parts module (see Standalone usage (without flake-parts) for non-flake-parts usage).
To get started, see Getting Started and thereon see Guide. To get inspired, see Examples. For reference, see Reference.