{"type":"post","id":"bitter-lessoned-in-automated-theorem-proving-13-minute-2e2a5c","slug":"bitter-lessoned-in-automated-theorem-proving-13-minute-2e2a5c","title":"Bitter Lessoned in Automated Theorem Proving (13 minute read)","description":"John Loeber published a first-person account of building an automated theorem prover around a private Lean4 fork.","retrieval_nugget":"John Loeber published a first-person account of building an automated theorem prover around a private Lean4 fork.","published_at":"2026-10-26","updated_at":"2026-10-26","record_date":"2026-10-26","date_kind":"published_at","topics":["harness-engineering","agent-runtime"],"entities":["John Loeber","Lean4","GPT-5.5","GPT-5.6 Sol","GPT-6 Astra","OpenAI"],"related_patterns":["harness-architecture-outlives-model-choice","verification-bandwidth-is-the-scarce-resource"],"novelty_label":"new_fact","what_changed":"Loeber adds a first-person account of building a private Lean4 theorem prover and argues that reasoning models plus formal verification make automated proof search newly viable.","prior_refs":["memory:ab7dd0e2-3563-87fc-a075-b5e0601978fe","memory:989f4ca1-492f-8157-a2e7-e4ae4d2a917a"],"source_url":"https://essays.johnloeber.com/p/34-bitter-lessoned-in-automated-theorem","source_urls":["https://essays.johnloeber.com/p/34-bitter-lessoned-in-automated-theorem"],"schema_version":"newruntime-agent-readable-v0.2","stable_id":"post:bitter-lessoned-in-automated-theorem-proving-13-minute-2e2a5c","status":"published","visuals":[],"editor":{"role":"editor","name":"Andrey Reshetnikov","profile":"https://newruntime.com/owner-profile.md","profile_json":"https://newruntime.com/owner-profile.json","same_as":["https://www.linkedin.com/in/reshetnikov1/","https://t.me/lapetuse"]},"routes":{"html":"https://newruntime.com/posts/bitter-lessoned-in-automated-theorem-proving-13-minute-2e2a5c/","markdown":"https://newruntime.com/posts/bitter-lessoned-in-automated-theorem-proving-13-minute-2e2a5c.md","json":"https://newruntime.com/posts/bitter-lessoned-in-automated-theorem-proving-13-minute-2e2a5c.json"},"next_reads":[{"type":"topic","path":"/topics/harness-engineering/","url":"https://newruntime.com/topics/harness-engineering/","title":"Harness Engineering","reason":"Explore the harness-engineering topic hub.","media_type":"text/html","markdown_url":"https://newruntime.com/topics/harness-engineering.md","json_url":"https://newruntime.com/topics/harness-engineering.json"},{"type":"topic","path":"/topics/agent-runtime/","url":"https://newruntime.com/topics/agent-runtime/","title":"Agent Runtime","reason":"Explore the agent-runtime topic hub.","media_type":"text/html","markdown_url":"https://newruntime.com/topics/agent-runtime.md","json_url":"https://newruntime.com/topics/agent-runtime.json"},{"type":"collection","path":"/posts/","url":"https://newruntime.com/posts/","title":"Field Notes","reason":"Open the latest editorial analysis.","media_type":"text/html","json_url":"https://newruntime.com/posts.json"},{"type":"collection","path":"/source-ledger.json","url":"https://newruntime.com/source-ledger.json","title":"Source Ledger","reason":"Inspect the public source evidence graph.","media_type":"application/json"}]}
