Karpathy's Autoresearch found a 3-year-old bug in our query engine (and improved performance by 11%) - PostHog

kept by eddie jun 03

PostHog used a Karpathy-style AI agent to find a 3-year-old ClickHouse bug where `toTimeZone()` disabled primary key usage, and the fix cut query time by 37%

Shopify/liquid: Performance: 53% faster parse+render, 61% fewer allocations
Shopify CEO Tobias Lütke used the autoresearch pattern with a coding agent to achieve 53% faster parse+render and 61% fewer allocations in the Liquid template engine.
also on #performance-optimization, autoresearch, pi, #ai-coding, #developer-tools
Pi, Minimal and Performant
Pi's minimal coding harness improves cost and performance by using fewer tools and less context, validated by Databricks' benchmark and Shopify's extensible pi-autoresearch extension.
also on pi-autoresearch, pi, #ai-coding, #software-engineering, #developer-tools
GitHub - LMCache/LMCache: Supercharge Your LLM with the Fastest KV Cache Layer
LMCache is a vendor-neutral KV cache management layer that reduces time-to-first-token and improves throughput for LLM inference by enabling persistent storage and reuse of cached states.
also on #performance-optimization
I rewrote PostHog's SQL parser, 70x faster, while barely looking at the code
PostHog's engineer used parallel Claude Code sessions to rewrite their SQL parser, achieving a 70x speedup by fuzzing against the old ANTLR-based parser as an oracle.
also on ClickHouse, PostHog, #database, #ai-coding, #software-engineering, #developer-tools
A new software engineering paradigm – Blog
Using formal verification, AI agents can generate code and machine‑checked proofs, removing the need for human code review and overcoming the AI‑generated‑code bottleneck.
also on autoresearch, Andrej Karpathy, #ai-coding, #software-engineering, #developer-tools