February 12, 2026
tl;dr
I tasked Claude, Codex, and Gemini to build a SQLite-like engine in Rust.
~19k~ lines of code.
lines of code. Parser, planner, volcano executor, pager, b+trees, wal, recovery, joins, aggregates, indexing, transaction semantics, grouped aggregates, and stats-aware planning all implemented.
282 unit tests, all passing.
background
Treat software engineering like distributed systems, and force coordination with: git, lock files, tests, and merge discipline.
harness
├── AGENT_PROMPT.md // main agent task prompt ├── BOOTSTRAP_PROMPT.md // bootstrap (initialization) prompt ├── COALESCE_PROMPT.md // deduplication prompt for coalescer agent ├── launch_agents.sh // launches all agents and sets up isolated workspaces ├── agent_loop.sh // per-agent loop/worker script ├── restart_agents.sh // restarts agents └── coalesce.sh // invokes the coalescing script
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