DevGen

Why DevGen

DevGen is a CLI for the parts of development that should be invisible. It writes Conventional Commits from your diff, drafts SemVer changelogs, fetches .gitignore and license templates, and routes everything through whichever AI provider you prefer — including a fully local Ollama model if you don't want to send code to the cloud.

Features

• AI-Powered Commits — Conventional Commit messages generated from your staged diff, grouped by directory, with optional emoji prefixes.
• Multiple Providers — Google Gemini, OpenAI, Anthropic, OpenRouter, HuggingFace, and local Ollama, all behind one CLI.
• Smart Caching — .gitignore and license templates are cached for offline use; AI responses are de-duplicated.
• Conventional Changelogs — feat, fix, refactor, perf, docs, test, build, ci, chore, style, and a BREAKING CHANGES section.
• Project Scaffolding — Pull .gitignore from GitHub's collection and drop in SPDX license files (MIT, Apache-2.0, GPL-3.0, AGPL-3.0, BSD, MPL-2.0, …).
• Custom Templates — Override the commit-message prompt via a .tpl file in your config.
• Interactive Setup — devgen setup walks you through provider + API key + options.
• Undo Support — devgen commit undo rolls back the last AI commit while keeping changes staged.
• Token-Limit Aware — When a diff exceeds a model's context window, you get a single actionable error with --max-groups and --max-diff-size hints.

Supported AI Providers

Installation

# Recommended: isolated environment
pipx install devgen-cli

# Or use uv for speed
uv tool install devgen-cli

# Or plain pip
pip install devgen-cli

# Shell completion (bash/zsh/fish)
devgen --install-completion

Requires Python 3.10 or newer.

Quick Start

# 1. Configure a provider and API key
devgen setup config

# 2. Stage your work as usual
git add .

# 3. Let DevGen write the commit message
devgen commit run

# 4. Or preview first, then commit
devgen commit run --dry-run
devgen commit run --push

Commands

Run devgen <command> --help for full options on any subcommand.

Custom Templates

DevGen uses .tpl files for its commit prompt. To override the default, set custom_template in your config (see devgen config info) and point it at a .tpl file with {{ diff_text }}, {{ context }}, {{ group_name }}, and the conditional {% if use_emoji %} block.

Example minimal template:

{{ diff_text }}
Summarize the change above in one Conventional Commit line.

Architecture

DevGen is built around a small set of composable components:

• BaseProvider — abstract base for every AI provider; handles API-key validation, token-limit detection, and error wrapping. Adding a new provider is one subclass with a single _generate() method.
• GitOperator — all subprocess calls to git live here, behind a GitError exception.
• DiffBuilder / FileGrouper / ManifestInspector — split a staged diff into per-directory groups with compact project context, so the model sees a focused slice instead of a wall of text.
• Section enum — single source of truth for changelog ordering and emoji, shared by ChangelogGenerator and ReleaseNotesGenerator.

The CLI entry point is devgen.cli.main:app (Typer), exposed as the devgen script.

Development

git clone https://github.com/S4NKALP/DevGen.git
cd DevGen
uv sync --all-extras --dev      # install runtime + dev deps
uv run pre-commit run --all-files
uv run devgen --help

The project uses uv for dependency management, ruff for lint + format, and pyright for type checking. CI runs all three on Python 3.10 through 3.13 (see .github/workflows/ci.yml).

Contributing

Issues and PRs welcome. Please run uv run pre-commit run --all-files before opening a PR so CI stays green.

License

GPL-3.0-or-later. See LICENSE.

Acknowledgments

Built on the shoulders of:

• Typer & Rich — CLI and terminal UI
• Questionary — interactive prompts
• Google Gemini, OpenAI, Anthropic, OpenRouter, HuggingFace, and Ollama — AI providers
• Ruff — lint and format