Contributing

Contributions to lash are welcome. This page covers the repository layout, build process, and conventions you need to follow.

Repository

• URL: https://gitlab.com/szabobogdan3/lash
• License: MIT

Build Requirements

Lash is written in DLang. You need one of the following compilers plus the dub package manager:

• LDC2 (recommended for release builds)
• DMD (faster compilation during development)

# Build
dub build

# Run tests
dub test

Architecture

Lash uses a five-layer architecture with strict downward-only dependencies:

runtime/   -> (nothing, only std library)
lang/      -> runtime/
protocol/  -> runtime/
backend/   -> lang/, protocol/, runtime/
frontend/  -> protocol/, runtime/   (never imports backend/)
plugins/   -> backend/plugin/base/, protocol/, runtime/

• runtime/ — pure types (LashValue, Scope, LashError), OS abstractions.
• lang/ — lexer, parser, evaluator, expansion, optimizer (turbo analysis/fusion/operations/heap).
• protocol/ — wire format (codec, encoders, decoders), transport, IPC.
• backend/ — execution (pipeline, redirects, streaming, PTY, turbo), daemon, session, config, hooks, plugins, script.
• frontend/ — terminal input, raw mode, key reader, completion, history, rendering, connection.

Code Constraints

These constraints are enforced across the entire codebase:

• No file may exceed 500 lines.
• Each file contains one struct/class or a cohesive group of free functions.
• No files named utils, helpers, or common.
• All structs, classes, and interfaces must have /// doc comments.

Test Suite

Lash has extensive test coverage:

Category	Count
Unit tests	~1600
Integration test files	11
.lash script tests	59
Blackbox tests (Python)	13

Run the full suite with:

dub test

Blackbox tests live under tests/ and require Python 3.

Adding a New Method

The evaluator method system has its own guide. See source/lash/lang/evaluator/methods/ADDING_METHODS.md for step-by-step instructions on registering a new built-in method, writing its implementation, and adding tests.

Workflow

1. Fork the repository on GitLab.
2. Create a feature branch from main.
3. Make your changes following the code constraints above.
4. Run dub test and ensure all tests pass.
5. Submit a merge request against main.