Jane Street

The Web’s Dirty Secret: Jane Street’s Bonsai Exposes the Functional Programming Fantasy

📅 August 3, 2026 📂 AI & Machine Learning

Jane Street’s Bonsai UI library is a masterpiece of functional programming – until it hits the browser. The firm had to build a userland trampoline to work around JavaScript’s lack of tail call optimization, exposing the brutal truth: the web is inherently hostile to functional purity, no matter how much money or talent you throw at it.

Bonsai Browser Constraints Engineering Trade-offs Functional Programming Jane Street JavaScript OCaml UI Libraries Web Platform

The 0.1% Rule: How Jane Street Builds Code That Runs 100x Faster by Doing Almost Nothing

📅 July 21, 2026 📂 Tech Industry

Jane Street’s Incremental framework doesn’t just optimize code — it changes the fundamental question you ask. Instead of ‘how can I make this computation faster?’, it asks ‘what computation actually needs to happen?’ The result is a system that runs 100x faster by doing almost nothing. The real lesson? Most performance problems aren’t about speed — they’re about scope.

DAGs Functional Programming High-Frequency Trading Incremental Computation Jane Street OCaml Performance Engineering Software Architecture