melt

A terminal UI for managing Nix flake inputs. View, update, and lock your flake inputs interactively.

Features

• View flake inputs - See all inputs with name, type, revision, and last modified time
• Check for updates - Background checks show how many commits each input is behind
• Update inputs - Update selected inputs or all at once
• View changelog - Browse commit history for any git input
• Lock to commit - Select a specific commit to lock an input to
• Multi-forge support - GitHub, GitLab, SourceHut, Codeberg, and generic git

Installation

With Nix

nix run github:anomalyco/melt-rs

Or add to your flake inputs:

{
  inputs.melt.url = "github:anomalyco/melt-rs";
}

From source

git clone https://github.com/anomalyco/melt-rs
cd melt-rs
nix develop
cargo build --release

Usage

# Run in current directory
melt

# Run in specific flake directory
melt /path/to/flake

Key Bindings

List View

Key	Action
j / ↓	Move down
k / ↑	Move up
Space	Toggle selection
u	Update selected inputs
U	Update all inputs
c	View changelog for current input
r	Refresh flake metadata
q / Esc	Quit

Changelog View

Key	Action
j / ↓	Move down
k / ↑	Move up
Space	Select commit for locking
y	Confirm lock to selected commit
n	Cancel lock
q / Esc	Back to list

Status Column

The STATUS column shows update status for git inputs:

• (empty) - Not yet checked
• ... - Currently checking
• ok - Up to date
• +N - N commits behind (e.g., +5 means 5 commits behind)

Architecture

src/
├── main.rs           # CLI entry point
├── app.rs            # Application state machine
├── tui.rs            # Terminal setup/teardown
├── event.rs          # Input handling
├── error.rs          # Error types
├── model/            # Data structures
│   ├── flake.rs      # FlakeData, FlakeInput, ForgeType
│   ├── commit.rs     # Commit, ChangelogData
│   └── status.rs     # UpdateStatus
├── service/          # Business logic
│   ├── nix.rs        # Nix flake commands
│   └── git.rs        # Git operations (via git2)
├── ui/               # Rendering
│   └── theme.rs      # Catppuccin Mocha colors
└── util/
    └── time.rs       # Relative time formatting

Development

# Enter dev shell
nix develop

# Run
cargo run -- /path/to/flake

# Test
cargo test

# Build release
cargo build --release

Environment Variables

Variable	Description
GITHUB_TOKEN	GitHub personal access token for API authentication
GH_TOKEN	Alternative to GITHUB_TOKEN (used by gh CLI)

Setting a GitHub token increases the API rate limit from 60 to 5000 requests/hour.

Requirements

• Nix with flakes enabled
• Git (for changelog features, via libgit2)
• SSH agent (for private repos)

License

MIT