id: task-210 title: Refactor Nix packaging to build node_modules offline status: Done assignee: [] created_date: '2025-07-26' updated_date: '2025-07-31' labels:

• nix
• build
• packaging dependencies: []

Description

Our current flake.nix runs 'bun install' inside the Nix build. Nix builds run without internet access, so trying to download tailwindcss and other dependencies in the build causes a 'connection refused' error. We need to refactor the Nix packaging to use bun2nix for native Bun lockfile support instead of maintaining dual lockfiles (bun.lock + package-lock.json).

Acceptance Criteria

• [x] The Nix flake uses bun2nix to generate dependencies from bun.lock instead of requiring separate package-lock.json
• [x] nix build succeeds in a clean sandbox (no network access) and produces a working backlog binary
• [x] nix run . -- --version prints the CLI version without errors on supported platforms
• [x] Only bun.lock is used for dependency management (no package-lock.json maintenance required)
• [x] Documentation in README or a scripts/ helper explains how to update dependencies when bun.lock changes

Implementation Plan

1. Research bun2nix integration patterns and current status
2. Add bun2nix as flake input and configure mkBunPackage
3. Remove generated package-lock.json and revert to native Bun approach
4. Test build works correctly in sandbox environment
5. Update documentation for dependency management workflow

Implementation Notes

Refactored Nix packaging to use bun2nix instead of the npm-based approach from PR #260. This eliminates the need to maintain dual lockfiles and provides native Bun ecosystem support.

Key changes:

• Added bun2nix flake input from github:baileyluTCD/bun2nix
• Replaced pkgs.stdenv.mkDerivation with bun2nix.lib.${system}.mkBunDerivation
• Configured to use existing bun.lock and package.json directly without requiring package-lock.json
• Removed network-dependent bun install --frozen-lockfile from build process
• Added comprehensive Nix installation documentation to README

The solution provides offline builds using bun2nix's dependency resolution while maintaining the existing Bun-based development workflow. Dependencies are now fetched in a separate derivation and cached, enabling reproducible builds in sandboxed environments.