Development Shells #

Reproducible development environments using Nix.

Available Shells #

Shell	Language	Version	Tools
python	Python	3.13	uv, black
java	Java	21	JDK
rust	Rust	stable	cargo, rustc
django	Python	3.13	uv, Django
chat	Python	3.13	uv, OpenAI SDK
stock-analysis	Python	3.13	uv, analysis libs
mcp-server	Python	3.14	uv, MCP SDK

Usage #

# Enter a shell
nix develop .#python

# Run command without entering
nix develop .#python --command python script.py

# List all shells
nix flake show | grep devShells

Structure #

Each shell is in devShells/<name>/default.nix:

{pkgs, ...}:
pkgs.mkShell {
  name = "shell-name";

  buildInputs = with pkgs; [
    package1
    package2
  ];

  shellHook = ''
    echo "Shell activated"
  '';
}

Adding a Shell #

1. Create devShells/myshell/default.nix:

{pkgs, ...}:
pkgs.mkShell {
  buildInputs = with pkgs; [
    nodejs
    yarn
  ];
}

2. Register in flake-modules/dev-shells.nix:

myshell = import ../devShells/myshell {
  inherit pkgs;
};

3. Test:

git add devShells/myshell flake-modules/dev-shells.nix
nix develop .#myshell

Notes #

• chat shell loads OpenAI API key from ~/.openai-key
• Shells work offline after first build
• Use direnv for automatic activation (add .envrc with use flake .#shell)