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DHH Proved Rust Beats Rails. He Never Read the Winning Code.
What did the DHH Rust Rails benchmark actually measure?
Rails performance vs Rust scored 36,260 to 241 in the Campfire test. It measured tuning effort per port, not language.
A Rust bar 150 times taller than the Rails bar is about to reach a CTO’s inbox with a rewrite budget attached. It comes from DHH’s Campfire test, where Rust served 36,260 requests per second against 241 for Rails, and the number that explains the gap is not on the chart.
The Register reported the results on October 7, 2026, and every Rails performance vs Rust headline since has skipped what the chart actually measured. It measured how much tuning each port received, and the person signing the budget will not open the repositories to check.
DHH had AI agents port Campfire, the 37signals group chat app, into Rust, Go and Elixir, then compared each port with the original Rails app. The Register reported that each rewrite took only a few hours.
The DHH Rust Rails benchmark has several tasks, and the room page is the one everyone quotes.
- Rust served 36,260 requests per second.
- Go served 3,860.
- Elixir served 722.
- Rails served 241.
