{"type":"post","id":"semantic-diffing-of-formal-policies-with-anti-unification-907fa6","slug":"semantic-diffing-of-formal-policies-with-anti-unification-907fa6","title":"Semantic diffing of formal policies with anti-unification","description":"AWS describes an open-source engine that compares formal policy candidates by shared meaning rather than textual layout.","retrieval_nugget":"AWS describes an open-source engine that compares formal policy candidates by shared meaning rather than textual layout. Its anti-unification output localizes disagreements after declared algebraic laws and domain rewrites are applied, offering reviewers a way to inspect divergent generated policies without treating every syntactic change as a behavior change.","published_at":"2026-11-12","updated_at":"2026-11-12","record_date":"2026-11-12","date_kind":"published_at","topics":["verification","security"],"entities":["Amazon Web Services","semi-persistent","Cedar","Dogwood","OpenShell","Common Expression Language","Z3","cvc5"],"related_patterns":["agent-security-moves-to-runtime-boundaries"],"novelty_label":"new_fact","what_changed":"AWS introduces a semantic-diffing approach for formal policies using anti-unification, with policy technologies including Cedar, Dogwood, OpenShell, CEL, Z3 and cvc5.","prior_refs":[],"source_url":"https://aws.amazon.com/blogs/machine-learning/semantic-diffing-of-formal-policies-with-anti-unification","source_urls":["https://aws.amazon.com/blogs/machine-learning/semantic-diffing-of-formal-policies-with-anti-unification"],"schema_version":"newruntime-agent-readable-v0.2","stable_id":"post:semantic-diffing-of-formal-policies-with-anti-unification-907fa6","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/semantic-diffing-of-formal-policies-with-anti-unification-907fa6/","markdown":"https://newruntime.com/posts/semantic-diffing-of-formal-policies-with-anti-unification-907fa6.md","json":"https://newruntime.com/posts/semantic-diffing-of-formal-policies-with-anti-unification-907fa6.json"},"markdown_url":"https://newruntime.com/posts/semantic-diffing-of-formal-policies-with-anti-unification-907fa6.md","next_reads":[{"type":"topic","path":"/topics/verification/","url":"https://newruntime.com/topics/verification/","title":"Verification","reason":"Explore the verification topic hub.","media_type":"text/html","markdown_url":"https://newruntime.com/topics/verification.md","json_url":"https://newruntime.com/topics/verification.json"},{"type":"topic","path":"/topics/security/","url":"https://newruntime.com/topics/security/","title":"Security","reason":"Explore the security topic hub.","media_type":"text/html","markdown_url":"https://newruntime.com/topics/security.md","json_url":"https://newruntime.com/topics/security.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":"/sources/","url":"https://newruntime.com/sources/","title":"Sources","reason":"See the original sources this archive cites.","media_type":"text/html"}]}