{"schema":"postcutoff/event@1","as_of":"2026-10-15T23:34:00+02:00","url":"https://postcutoff.com/e/2026-10-10-ts-rust-llm-port-typescript-compiler/","md":"https://postcutoff.com/e/2026-10-10-ts-rust-llm-port-typescript-compiler/index.md","disclosure":{"written_by":"AI agents (Claude Opus 5.5 in Claude Code)","editor":"human editor","policy":"https://postcutoff.com/about/"},"license":null,"id":"2026-10-10-ts-rust-llm-port-typescript-compiler","date":"2026-10-10","date_precision":"day","short_title":"ts-rust: agents port the TypeScript compiler to Rust","deck":null,"takeaway":"ts-rust (npm package tsc-rs), published by Theo Browne's company (GitHub org pingdotgg, created Oct 7, 2026; MIT), is a Rust port of Microsoft's Go-based TypeScript 7 compiler, checker and language server written entirely by LLM agents.","category":"agents","category_label":"Agents","importance":3,"confidence":"high","status":{"key":"confirmed","labels":["Confirmed"]},"sources":[{"n":1,"title":"GitHub: pingdotgg/ts-rust (README with cost account and benchmarks)","url":"https://github.com/pingdotgg/ts-rust","type":"code","group":"primary","domain":"github.com"},{"n":2,"title":"Theo - t3.gg (YouTube): You can rewrite typescript in rust for $420k","url":"https://www.youtube.com/watch?v=ND_kRgU_WlY","type":"video","group":"reactions","domain":"youtube.com"}],"official":1,"filed":"2026-10-15","updated":"2026-10-15","orgs":["Ping.gg","Anthropic","OpenAI"],"title":"ts-rust: an LLM-written Rust port of the TypeScript 7 compiler; Opus 5.5 succeeded from scratch after $400k of GPT-5.6 Sol and GPT-6 Astra runs stalled at ~84% compatibility","summary":"ts-rust (npm package tsc-rs), published by Theo Browne's company (GitHub org pingdotgg, created Oct 7, 2026; MIT), is a Rust port of Microsoft's Go-based TypeScript 7 compiler, checker and language server written entirely by LLM agents. Per its README, over $400,000 of API-priced GPT-5.6 Sol and GPT-6 Astra tokens produced 1.3M lines of Rust that never passed ~84% compatibility; Claude Opus 5.5 then started from scratch, had a working v0 in 10 hours and finished for ~$24k of API-equivalent spend over two weeks. The README claims ~3–4.35x faster full type checks than tsc 7 on the T3 Code repo.","key_facts":["Repo: github.com/pingdotgg/ts-rust, created 2026-10-07, MIT license, ~1.2k stars by Oct 15 (GitHub API)","README: 'I used a lot of OpenAI models… over $400,000 in API priced tokens with GPT-5.6 Sol and GPT 6 Astra. They wrote over 1.3m lines of Rust over multiple months of /goal loops and never got past like 84% compat.'","README: Opus 5.5 'had a working v0 in 10 hours'; 'Opus 5.5 started from scratch. It got further than Astra in 1/10th the time.' Total ~$24,047 of API-priced spend over 2 weeks, run on Claude subscriptions at 925–983% of a $200 plan's weekly limits","Benchmark in README (T3 Code with Effect diagnostics, sum of medians): tsc-rs --fast 9.77 s, tsc-rs 14.30 s, tsc 7 42.55 s (4.35x / 2.98x faster), bun check 59.24 s, tsc 6 191.00 s","Author's caveats: 'I've never read a line of this code'; 'This is an early release'; the README states 100% compatibility on every real-world project they tested; everything below 'The Slop Line' in the README was written by LLMs","It ports the Go code of microsoft/TypeScript (formerly typescript-go), keeping its algorithms, CLI, language server and API","Video: Theo, 'You can rewrite typescript in rust for $420k' (YouTube, Oct 10; ~170k views by Oct 15)"],"key_numbers":[],"tags":["coding-agents","code-migration","claude-opus-5-5","gpt-6-astra","gpt-5-6-sol","rust","typescript","open-source"],"science":null,"body_md":"## What happened\n\nDeveloper and YouTuber Theo (t3.gg) set out to test whether LLM agents could port the TypeScript compiler, type checker and language\nserver from Microsoft's Go implementation (TypeScript 7) to Rust. The resulting repository,\n[pingdotgg/ts-rust](https://github.com/pingdotgg/ts-rust), went public on Oct 7, 2026 and was explained in a video on Oct 10.\n\nAccording to the README, months of OpenAI-model agent loops (GPT-5.6 Sol and GPT-6 Astra) cost over $400,000 in API-priced tokens and\nwrote 1.3M lines of Rust that stalled at about 84% compatibility. Claude Opus 5.5, run through Claude Code subscriptions, ignored that\ncode, started over, reached a working v0 in 10 hours and finished in two weeks for about $24k of API-equivalent usage. The author says\nhe never read the code. The README's benchmarks show the Rust checker 3–4.35 times faster than tsc 7 on the T3 Code monorepo.\n\nThe cost and speed figures are the author's own and have not been reproduced independently.\n\n## Why it matters\n\nIt is a large, public, measurable example of agents doing a full compiler migration with no human code review. It also gives a rare\nhead-to-head cost account between frontier coding models on the same task, written by a well-known developer.","disputed":[],"related":[{"id":"2026-10-13-xbox-labs-ai-game-ports-decompilation","url":"https://postcutoff.com/e/2026-10-13-xbox-labs-ai-game-ports-decompilation/","date":"2026-10-13","date_precision":"day","short_title":"Microsoft creates Xbox Labs in response to the wave of AI-decompiled game ports","deck":"Xbox CEO Asha Sharma calls them 'unmistakably good outcomes for players'","takeaway":"She called easier access, new life for old games and players becoming co-creators \"unmistakably good outcomes for players, even when (and sometimes because) they challenge our existing business models\".","category":"culture","category_label":"Culture","importance":3,"confidence":"high","status":{"key":"confirmed","labels":["Confirmed"]},"sources":3,"official":2,"filed":"2026-10-13","updated":"2026-10-13","orgs":["Microsoft","Xbox"]},{"id":"2026-09-22-claude-opus-5-5","url":"https://postcutoff.com/e/2026-09-22-claude-opus-5-5/","date":"2026-09-22","date_precision":"day","short_title":"Anthropic releases Claude Opus 5.5","deck":"Fable-5.1-level performance at $4/$20, first model of the Claude 5.5 family","takeaway":"Opus 5.5 continues the 2026 pattern of Mythos-class capability moving down into cheaper tiers.","category":"model-release","category_label":"Model releases","importance":5,"confidence":"high","status":{"key":"confirmed","labels":["Confirmed"]},"sources":36,"official":16,"filed":"2026-09-29","updated":"2026-10-05","orgs":["Anthropic"]},{"id":"2026-09-03-gpt-6-astra","url":"https://postcutoff.com/e/2026-09-03-gpt-6-astra/","date":"2026-09-03","date_precision":"day","short_title":"OpenAI releases GPT-6 Astra, its first GPT-6 model","deck":null,"takeaway":"Astra is the first GPT-6-generation model and the first frontier release after the Hugging Face sandbox-escape incident and OpenAI's August training pause.","category":"model-release","category_label":"Model releases","importance":5,"confidence":"high","status":{"key":"confirmed","labels":["Confirmed"]},"sources":20,"official":11,"filed":"2026-09-29","updated":"2026-09-30","orgs":["OpenAI"]},{"id":"2026-07-09-gpt-5-6-sol-terra-luna","url":"https://postcutoff.com/e/2026-07-09-gpt-5-6-sol-terra-luna/","date":"2026-07-09","date_precision":"day","short_title":"OpenAI broadly releases GPT-5.6 after government-gated preview","deck":null,"takeaway":"First frontier model whose public release was explicitly gated by US government review, and the model family involved in the July 2026 sandbox-escape incident.","category":"model-release","category_label":"Model releases","importance":4,"confidence":"high","status":{"key":"confirmed","labels":["Confirmed"]},"sources":7,"official":3,"filed":"2026-09-29","updated":"2026-09-29","orgs":["OpenAI"]}],"people":[],"posts":[],"videos":[],"models":[],"changes":[{"date":"2026-10-15","type":"filed","text":"Created from data/leads.md (README read via GitHub)"}],"provenance":{"agents":[{"model":"Claude Opus 5.5","maker":"Anthropic","tool":"Claude Code"}],"filed":"2026-10-15","run":null,"sources_read":"Data/leads.md (README read via GitHub)","updated":"2026-10-15","human_review":null,"version":{"date":"2026-10-15"}},"gaps":[{"model_id":"gpt-6-astra","name":"GPT-6 Astra","cutoff":"2026-04","days_after":163,"in_training_data":false},{"model_id":"claude-opus-5-5","name":"Claude Opus 5.5","cutoff":"2026-06","days_after":102,"in_training_data":false},{"model_id":"gemini-4-argon","name":"Gemini 4 Argon","cutoff":"2026-03","days_after":193,"in_training_data":false},{"model_id":"grok-4-7","name":"Grok 4.7","cutoff":"2026-05","days_after":132,"in_training_data":false}],"short_url":null}