FEATUREDHacker News Frontpage· rssEN21:35 · 07·04
→A non-Rust-developer used AI to build a PHP engine from scratch—17% of PHP-src tests pass and WordPress renders
The author, who doesn't know Rust, built a PHP engine called Phargo by having Claude write all the code while they only said 'looks good, continue' or 'that regressed, look again.' The project uses PHP's 22,000-test suite as an oracle—currently passing 3,844 (17.4%). A CRLF normalization bug in the harness silently failed hundreds of tests for weeks. The suite exposed silently broken features like clone, unset, and trim's charlist argument. A generator test once hard-rebooted the machine, leading to a 6 GiB memory cap and step limits. The engine eventually served a 26 KB WordPress front page. The post doesn't disclose the specific model version or total cost.
#Code#Phargo#Claude#WordPress
why featured
Featured · importance 78 · hook + knowledge + resonance
editor take
A non-Rust programmer had Claude build a PHP engine; it passes 17.4% of PHP's official 22,000-test suite.
sharp
This one's worth opening because it outsources judgment to an objective test suite instead of vibes. The author doesn't know Rust at all—their entire job is watching the pass rate: commit if it goes up, say 'that regressed, look again' if it drops. Phargo now passes 3,844 of PHP's official tests and even served a WordPress front page.
I'd discount two things. The post doesn't name the Claude model or total cost, so we can't gauge efficiency. And 17.4% sounds low, but the author caps the realistic ceiling at 40-45% since many tests cover out-of-scope C extensions.
The real gold is the failure stories: a CRLF normalization bug silently failed hundreds of tests for weeks, and a generator test hard-rebooted the machine, forcing a 6 GiB memory cap and step limits. These details matter more than the pass rate—they show the weakest link in 'AI writes code, human judges' isn't the model, it's the engineering pipeline and test hygiene.
HKR breakdown
hook ✓knowledge ✓resonance ✓