Zerobrew v0: Complete Implementation (Steps 2-10)

[lucasgelfond]

Summary

Complete implementation of Zerobrew v0 - a fast Homebrew-compatible package installer for macOS arm64.

Phases Implemented

Phase	Steps	Description
2	2.1-2.2	API client with ETag caching
3	3.1-3.3	Blob cache, parallel downloads
4	4.1-4.2	Safe tar extraction, store entries
5	5.1-5.2	Materializer with APFS clonefile
6	6.1-6.2	Executable linking, SQLite state
7	7.1	Install command wiring
8	8.1-8.2	Uninstall & garbage collection
9	9.1-9.2	Benchmarking tool
10	10.1	CLI for daily driver use

Key Features

• Parallel downloads with bounded concurrency
• Single-flight deduplication for duplicate requests
• Content-addressed store with file locking
• APFS clonefile with hardlink/copy fallback
• Safe tar extraction (rejects path traversal)
• SQLite install state with transactions
• ETag-based API caching

CLI Usage

zb install <formula>    # Install with dependencies
zb uninstall <formula>  # Uninstall formula  
zb list                 # List installed formulas
zb info <formula>       # Show formula info
zb gc                   # Garbage collect store

Test Results

• 52 tests passing
• Clippy clean
• Smoke benchmark: ~10ms

Test plan

• cargo test --all passes
• cargo clippy --all-targets -- -D warnings passes
• zb bench smoke completes in < 60s
• zb install python3 works on macOS arm64

🤖 Generated with Claude Code