Pinning and Index

Primary Pin

The primary nixpkgs pin is stored in state and used for generation and index building.

Update it:

mica update --latest

Or target a specific file/global profile directly:

mica --file ./default.nix update --latest
mica --global update --latest

For explicit pin values:

mica update --url https://github.com/jpetrucciani/nix --branch main --rev <rev> --sha256 <sha>

Advanced Pins (Optional)

Extra pin workflows are available, but most users can ignore them:

mica pin --help

Package Index

Mica maintains a local SQLite index at:

~/.config/mica/cache/index.db

When index.remote_url is configured as a base URL, mica tries:

1. <remote_url>/<nixpkgs_commit>.db

If it does not exist, mica falls back to rebuilding locally.

Useful commands:

mica index status
mica index rebuild /tmp/nixpkgs.json
mica index rebuild-local ~/dev/jpetrucciani-nix --skip-attr home-packages,watcher --show-trace
mica index fetch

Versions Database

Mica also tracks package version history in:

~/.config/mica/cache/versions.db

This powers version-aware workflows in the TUI.

Index-related Environment Variables

• MICA_KEEP_INDEX_NIX=1 keeps temporary index input files for debugging
• MICA_NIX_SKIP_ATTRS=a,b,c skips problematic attrs when evaluating index sources
• MICA_NIX_SHOW_TRACE=1 enables --show-trace for nix evaluation