{"schema_version":"newruntime-agent-readable-v0.2","type":"raw_signal","stable_id":"signal:lean-zstd-proof-automation","id":"nr-f54dc79b-9f58-4e46-8532-96e3caca804e","slug":"lean-zstd-proof-automation","title":"LLMs Make Lean Proofs a Retryable Engineering Loop","description":"ImperialViolet's zstd-in-Lean experiment shows proof automation becoming practical when the model can generate attempts and Lean provides strict deterministic verification.","retrieval_nugget":"ImperialViolet's zstd-in-Lean experiment shows proof automation becoming practical when the model can generate attempts and Lean provides strict deterministic verification. The signal shifts formal methods from rare expert ceremony toward a generator-verifier loop: LLMs can fail repeatedly while Lean cheaply rejects bad proofs and accepts only type-checking ones. Novelty is structural; verification is source-inspected.","observed_at":"2026-07-28","record_date":"2026-07-28","date_kind":"observed_at","why_it_matters":"The signal shifts formal methods from rare expert ceremony toward a generator-verifier loop: LLMs can fail repeatedly while Lean cheaply rejects bad proofs and accepts only type-checking ones.","novelty":"structural","verification_level":"source-inspected","signal_type":"operating-model","evidence_kind":"primary-source","status":"published","source_platform":"curated","source_record_id":"f54dc79b-9f58-4e46-8532-96e3caca804e","source_url":"https://www.imperialviolet.org/2026/07/26/zstd-lean.html","topics":["lean","formal-verification","verification"],"entities":["ImperialViolet","Lean","Zstandard"],"related_patterns":["verification-bandwidth-is-the-scarce-resource","harness-architecture-outlives-model-choice","agent-ready-software-exposes-capabilities"],"source_urls":["https://www.imperialviolet.org/2026/07/26/zstd-lean.html"],"routes":{"html":"https://newruntime.com/signals/lean-zstd-proof-automation/","markdown":"https://newruntime.com/signals/lean-zstd-proof-automation.md","json":"https://newruntime.com/signals/lean-zstd-proof-automation.json"},"source_format":"editorial-normalized-json","next_reads":[{"type":"pattern","path":"/patterns/verification-bandwidth-is-the-scarce-resource/","reason":"Pattern connected to this observed signal.","url":"https://newruntime.com/patterns/verification-bandwidth-is-the-scarce-resource/","title":"Verification bandwidth is the scarce engineering resource","media_type":"text/html"},{"type":"pattern","path":"/patterns/harness-architecture-outlives-model-choice/","reason":"Pattern connected to this observed signal.","url":"https://newruntime.com/patterns/harness-architecture-outlives-model-choice/","title":"Harness architecture outlives model choice","media_type":"text/html"},{"type":"pattern","path":"/patterns/agent-ready-software-exposes-capabilities/","reason":"Pattern connected to this observed signal.","url":"https://newruntime.com/patterns/agent-ready-software-exposes-capabilities/","title":"Agent-ready software exposes capabilities","media_type":"text/html"},{"type":"topic","path":"/topics/verification/","reason":"Explore the verification topic hub.","url":"https://newruntime.com/topics/verification/","title":"Verification - New Runtime","media_type":"text/html"},{"type":"related_material","path":"/signals/cheap-code-moves-bottleneck-to-review/","reason":"Shares verification.","url":"https://newruntime.com/signals/cheap-code-moves-bottleneck-to-review/","title":"Cheap code moves the engineering bottleneck to review","media_type":"text/html"}]}