{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2026:4EQKBPBKYHOMHB2MBSPTC3LOIK","short_pith_number":"pith:4EQKBPBK","canonical_record":{"source":{"id":"2606.20121","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LO","submitted_at":"2026-06-18T11:45:25Z","cross_cats_sorted":[],"title_canon_sha256":"47d1728c33e172e1f6d27f5bb6f11bcbdf52af7eaf3ddaaf719ddd727aeeed18","abstract_canon_sha256":"b0e371103c1561e1866c56dd1b3872058a8c61a0f2e23c5b10c70e80939b98aa"},"schema_version":"1.0"},"canonical_sha256":"e120a0bc2ac1dcc3874c0c9f316d6e4282adffe17204977f01f45485c67767b8","source":{"kind":"arxiv","id":"2606.20121","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2606.20121","created_at":"2026-06-19T16:13:03Z"},{"alias_kind":"arxiv_version","alias_value":"2606.20121v1","created_at":"2026-06-19T16:13:03Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2606.20121","created_at":"2026-06-19T16:13:03Z"},{"alias_kind":"pith_short_12","alias_value":"4EQKBPBKYHOM","created_at":"2026-06-19T16:13:03Z"},{"alias_kind":"pith_short_16","alias_value":"4EQKBPBKYHOMHB2M","created_at":"2026-06-19T16:13:03Z"},{"alias_kind":"pith_short_8","alias_value":"4EQKBPBK","created_at":"2026-06-19T16:13:03Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2026:4EQKBPBKYHOMHB2MBSPTC3LOIK","target":"record","payload":{"canonical_record":{"source":{"id":"2606.20121","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LO","submitted_at":"2026-06-18T11:45:25Z","cross_cats_sorted":[],"title_canon_sha256":"47d1728c33e172e1f6d27f5bb6f11bcbdf52af7eaf3ddaaf719ddd727aeeed18","abstract_canon_sha256":"b0e371103c1561e1866c56dd1b3872058a8c61a0f2e23c5b10c70e80939b98aa"},"schema_version":"1.0"},"canonical_sha256":"e120a0bc2ac1dcc3874c0c9f316d6e4282adffe17204977f01f45485c67767b8","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-06-19T16:13:03.337000Z","signature_b64":"B1yw7J8abHvY40LqbAodpXe0Jtv5R3E5QW1jneBHRfUhDPT1MpZEqkcQuqcZPYEzch4Ux36ilQIqba+FrqXMCA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"e120a0bc2ac1dcc3874c0c9f316d6e4282adffe17204977f01f45485c67767b8","last_reissued_at":"2026-06-19T16:13:03.336596Z","signature_status":"signed_v1","first_computed_at":"2026-06-19T16:13:03.336596Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2606.20121","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-06-19T16:13:03Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"94wm+pLj/wU9FZW/vawcsupTqnhHopT/vYoTHT/vzO53fuBb0Km9p4jXXax+PmNjZFCSSrEZ+irOTbL4cb2FBg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-02T05:00:35.944964Z"},"content_sha256":"3097759e314dd33d39ff277a0a2f7522bf19df9ce316eb0bea9315381e27d694","schema_version":"1.0","event_id":"sha256:3097759e314dd33d39ff277a0a2f7522bf19df9ce316eb0bea9315381e27d694"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2026:4EQKBPBKYHOMHB2MBSPTC3LOIK","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"BARReL: a modern backend for Atelier B in Lean","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"cs.LO","authors_text":"Ghilain Bergeron, Vincent Tr\\'elat","submitted_at":"2026-06-18T11:45:25Z","abstract_excerpt":"BARReL is a Lean 4 library bridging Atelier B, an industrial tool for the B method, and the Lean proof assistant by enabling users to conduct their formal B developments -- up to machine refinement and implementation -- interactively inside Lean, while retaining standard B syntax. B partial operators are carefully encoded by generating explicit well-definedness conditions, leveraging Lean's dependent types to enforce a well-definedness discipline by construction. That is, proof obligations and proof steps cannot silently rely on ill-typed or ill-defined instantiations. BARReL also features bas"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2606.20121","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2606.20121/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-06-19T16:13:03Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"QOZoagDJ/80KEEzR4R2yu6SOIY5hCoHrxQkvrzdfnsOHxMqPLqrCl5I+7SeECXspZzQWcGFJCcxej9rt0bPACw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-02T05:00:35.945355Z"},"content_sha256":"a3c513a81812a997dc86c728aa2cb1a83baaa932c64bc0cdb4fe6b2817c5179a","schema_version":"1.0","event_id":"sha256:a3c513a81812a997dc86c728aa2cb1a83baaa932c64bc0cdb4fe6b2817c5179a"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/4EQKBPBKYHOMHB2MBSPTC3LOIK/bundle.json","state_url":"https://pith.science/pith/4EQKBPBKYHOMHB2MBSPTC3LOIK/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/4EQKBPBKYHOMHB2MBSPTC3LOIK/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-07-02T05:00:35Z","links":{"resolver":"https://pith.science/pith/4EQKBPBKYHOMHB2MBSPTC3LOIK","bundle":"https://pith.science/pith/4EQKBPBKYHOMHB2MBSPTC3LOIK/bundle.json","state":"https://pith.science/pith/4EQKBPBKYHOMHB2MBSPTC3LOIK/state.json","well_known_bundle":"https://pith.science/.well-known/pith/4EQKBPBKYHOMHB2MBSPTC3LOIK/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2026:4EQKBPBKYHOMHB2MBSPTC3LOIK","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"b0e371103c1561e1866c56dd1b3872058a8c61a0f2e23c5b10c70e80939b98aa","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LO","submitted_at":"2026-06-18T11:45:25Z","title_canon_sha256":"47d1728c33e172e1f6d27f5bb6f11bcbdf52af7eaf3ddaaf719ddd727aeeed18"},"schema_version":"1.0","source":{"id":"2606.20121","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2606.20121","created_at":"2026-06-19T16:13:03Z"},{"alias_kind":"arxiv_version","alias_value":"2606.20121v1","created_at":"2026-06-19T16:13:03Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2606.20121","created_at":"2026-06-19T16:13:03Z"},{"alias_kind":"pith_short_12","alias_value":"4EQKBPBKYHOM","created_at":"2026-06-19T16:13:03Z"},{"alias_kind":"pith_short_16","alias_value":"4EQKBPBKYHOMHB2M","created_at":"2026-06-19T16:13:03Z"},{"alias_kind":"pith_short_8","alias_value":"4EQKBPBK","created_at":"2026-06-19T16:13:03Z"}],"graph_snapshots":[{"event_id":"sha256:a3c513a81812a997dc86c728aa2cb1a83baaa932c64bc0cdb4fe6b2817c5179a","target":"graph","created_at":"2026-06-19T16:13:03Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2606.20121/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"BARReL is a Lean 4 library bridging Atelier B, an industrial tool for the B method, and the Lean proof assistant by enabling users to conduct their formal B developments -- up to machine refinement and implementation -- interactively inside Lean, while retaining standard B syntax. B partial operators are carefully encoded by generating explicit well-definedness conditions, leveraging Lean's dependent types to enforce a well-definedness discipline by construction. That is, proof obligations and proof steps cannot silently rely on ill-typed or ill-defined instantiations. BARReL also features bas","authors_text":"Ghilain Bergeron, Vincent Tr\\'elat","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LO","submitted_at":"2026-06-18T11:45:25Z","title":"BARReL: a modern backend for Atelier B in Lean"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2606.20121","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:3097759e314dd33d39ff277a0a2f7522bf19df9ce316eb0bea9315381e27d694","target":"record","created_at":"2026-06-19T16:13:03Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"b0e371103c1561e1866c56dd1b3872058a8c61a0f2e23c5b10c70e80939b98aa","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LO","submitted_at":"2026-06-18T11:45:25Z","title_canon_sha256":"47d1728c33e172e1f6d27f5bb6f11bcbdf52af7eaf3ddaaf719ddd727aeeed18"},"schema_version":"1.0","source":{"id":"2606.20121","kind":"arxiv","version":1}},"canonical_sha256":"e120a0bc2ac1dcc3874c0c9f316d6e4282adffe17204977f01f45485c67767b8","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"e120a0bc2ac1dcc3874c0c9f316d6e4282adffe17204977f01f45485c67767b8","first_computed_at":"2026-06-19T16:13:03.336596Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-06-19T16:13:03.336596Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"B1yw7J8abHvY40LqbAodpXe0Jtv5R3E5QW1jneBHRfUhDPT1MpZEqkcQuqcZPYEzch4Ux36ilQIqba+FrqXMCA==","signature_status":"signed_v1","signed_at":"2026-06-19T16:13:03.337000Z","signed_message":"canonical_sha256_bytes"},"source_id":"2606.20121","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:3097759e314dd33d39ff277a0a2f7522bf19df9ce316eb0bea9315381e27d694","sha256:a3c513a81812a997dc86c728aa2cb1a83baaa932c64bc0cdb4fe6b2817c5179a"],"state_sha256":"2636ca622e7ad0b52f063c898b99bc1bf8c8b567f04bd9ae35f87b1fe17939be"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"H9Feo8lOJHdnGGjOvwVXCmfNqSOfY2huYXsrCroSMMJZ8tbyz9w1uKJjDCD9f+Hx4kowyqdc6y0ZsuoNgMZuDQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-07-02T05:00:35.947518Z","bundle_sha256":"8cfb0651a90fe4c617ebd2ea161529c1f7cab3d507d48bb71377c5a0d8b88d16"}}