--- title: Claude Wrote a C Compiler that Couldn't Compile... ? description: Anthropic's Claude Code attempted to build a C compiler in Rust using 16 AI agents, producing 501 commits and thousands of files targeting four CPU... canonical: https://daily.dev/posts/claude-wrote-a-c-compiler-that-couldn-t-compile--k2lqikwfs twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Claude Wrote a C Compiler that Couldn't Compile... ? | daily.dev og:description: Anthropic's Claude Code attempted to build a C compiler in Rust using 16 AI agents, producing 501 commits and thousands of files targeting four CPU... og:url: https://daily.dev/posts/claude-wrote-a-c-compiler-that-couldn-t-compile--k2lqikwfs og:image: https://api.daily.dev/og/posts/k2lqIKWfs.png og:image:alt: Claude Wrote a C Compiler that Couldn't Compile... ? og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Claude Wrote a C Compiler that Couldn't Compile... ? **[Tech With Tim](https://daily.dev/sources/TechWithTim)** · 13 min read · 0 upvotes · 0 comments ## Summary Anthropic's Claude Code attempted to build a C compiler in Rust using 16 AI agents, producing 501 commits and thousands of files targeting four CPU architectures. However, the resulting compiler couldn't compile even a simple Hello World program, with bugs in ARM/x86 assemblers, missing C11 features, and no working build across any commit. A company called Blitzy then fixed all critical issues in the original repo and built an entirely new C compiler from scratch using their own multi-agent orchestration platform. Their BlitzCC compiler generated ~230,000 lines of Rust, passed 2,271 tests with zero failures, and successfully compiled SQLite, Lua, and the Linux kernel — all with just two human prompts versus 2,000 interactive turns required by Anthropic's approach. The key takeaway is that agent orchestration methodology matters enormously: Blitzy's approach of building a deep codebase knowledge graph and running thousands of parallel QA-checked agents over days outperformed Claude Code's more interactive, human-guided workflow. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Building a C compiler with a team of parallel Claudes](https://daily.dev/posts/building-a-c-compiler-with-a-team-of-parallel-claudes-gdolsqfbx) · Hacker News · 0 upvotes · 0 comments - [GitHub and Anthropic used their own agents for major Rust rewrites — with very different playbooks](https://daily.dev/posts/github-and-anthropic-used-their-own-agents-for-major-rust-rewrites-with-very-different-playbooks-vadg1uged) · The New Stack · 3 upvotes · 2 comments - [Anthropic's AI‑built C compiler is not all that impressive](https://daily.dev/posts/anthropic-s-ai-built-c-compiler-is-not-all-that-impressive-mzhhw9xzp) · The Register · 0 upvotes · 0 comments --- Tags: [#rust](https://daily.dev/tags/rust), [#ai-agents](https://daily.dev/tags/ai-agents), [#compiler](https://daily.dev/tags/compiler), [#claude-code](https://daily.dev/tags/claude-code) [View this post on daily.dev](https://daily.dev/posts/claude-wrote-a-c-compiler-that-couldn-t-compile--k2lqikwfs) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Claude Wrote a C Compiler that Couldn't Compile... ?","url":"https://daily.dev/posts/claude-wrote-a-c-compiler-that-couldn-t-compile--k2lqikwfs","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/claude-wrote-a-c-compiler-that-couldn-t-compile--k2lqikwfs"},"datePublished":"2026-04-10T14:17:33.978Z","dateModified":"2026-04-10T14:17:58.246Z","description":"Anthropic's Claude Code attempted to build a C compiler in Rust using 16 AI agents, producing 501 commits and thousands of files targeting four CPU...","image":"https://i.ytimg.com/vi/GtTJ6LcqdCE/sddefault.jpg","thumbnailUrl":"https://i.ytimg.com/vi/GtTJ6LcqdCE/sddefault.jpg","isAccessibleForFree":true,"articleSection":"Tech With Tim","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Tech With Tim","logo":"https://media.daily.dev/image/upload/s--6vVIDfU0--/f_auto/v1711726146/logos/TechWithTim","url":"https://daily.dev/sources/TechWithTim"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/claude-wrote-a-c-compiler-that-couldn-t-compile--k2lqikwfs","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"rust,ai-agents,compiler,claude-code","timeRequired":"PT13M","video":{"@type":"VideoObject","name":"Claude Wrote a C Compiler that Couldn't Compile... ?","description":"Anthropic's Claude Code attempted to build a C compiler in Rust using 16 AI agents, producing 501 commits and thousands of files targeting four CPU...","thumbnailUrl":"https://i.ytimg.com/vi/GtTJ6LcqdCE/sddefault.jpg","uploadDate":"2026-04-10T14:17:33.978Z","duration":"PT13M","url":"https://api.daily.dev/r/k2lqIKWfs","embedUrl":"https://www.youtube.com/embed/GtTJ6LcqdCE"}} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Tech With Tim","item":"https://daily.dev/sources/TechWithTim"},{"@type":"ListItem","position":3,"name":"Claude Wrote a C Compiler that Couldn't Compile... ?"}]} ```