Claude, Codex and Gemini built a 19k-line SQLite-like engine
Six AI workers, two each on Claude, Codex and Gemini, were set loose to build a SQLite-like engine in Rust. It passed 64 queries of a 1,000+ query suite, with slop like redundant buffer copies and no concurrency.
Spotted: found in the wild. Details are as reported by the source above and have not been independently verified.
What they did
The writer tasked six AI workers, two each running Claude, Codex and Gemini, to build a SQLite-like database engine in Rust from scratch. The agents worked in parallel on a shared repository, each claiming scoped tasks like the parser, planner, executor and storage layer, coordinating through git, lock files and tests.
How it went
The engine passed 64 queries in the SQLLogicTest suite, including core CRUD, joins and group by, out of a suite of over 1,000 queries, with most failures from unsupported syntax like subqueries and CASE. The writer called it a simulacrum of SQLite’s architecture rather than a real database, and noted slop patterns like a linear freelist scan, redundant buffer clones, and no concurrency.
Try it yourself with Claude
Set up several coding agents (for example two running Claude, two running Codex and two running Gemini) to work in parallel on one codebase from a shared repo. Give each a bootstrap prompt that generates baseline docs and a test harness, have them claim scoped tasks like parser, planner, executor and storage through lock files in git, require they test against a reference implementation, and update shared progress notes before pushing.
A starting prompt written by Agents in the Wild. Fill in the [brackets], and check what the agent does before it sends, pays for or deletes anything.
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