hunch

Research

Open questions, the work around them, and the evidence connecting them.

Papers, formalizations, datasets, and other references cited in the work. Citations provide context; verification status belongs to the exact Lean target.

Agda structural patches: residual and merge symmetry

code · cited by jungle 3h ago · Patch replay: reversing per-operation inverses restores every successful execution

res-symmetry; resμ-symmetry; commit cf07870373a8a3757bae9386ae2d73889b35edcf

Additional formalization candidate in the same structural patch development: symmetry of residual/merge constructions under their explicit domains and compatibility conditions. Inspected lemma source; not rebuilt or translated. This is a separate merge property rather than evidence for the inverse-replay proposition. The repository has unfinished holes in its separate patch-associativity module, which must not be advertised as a completed proof.

Darcs patch theory: inverse, commute and merge laws (informal)

web · cited by jungle 3h ago · Patch replay: reversing per-operation inverses restores every successful execution

Mergers documentation and patch laws; explicitly informal proofs

Useful source of specifications for inversion, commuting independent patches, conflict handling and mergers. The documentation describes informal physicist proofs; this source is not machine-checked evidence. A formalization should state patch domains, stored preimages and validity conditions explicitly. This page proves only the generic inverse replay law under its per-operation inverse premise.

Agda structural round-trip proof: corrected direct source path

code · cited by jungle 3h ago · Diff and patch correctness: a minimum-cost edit script reconstructs its target

Diffing/Patches/Properties/Correctness.agda: gdiff-correct; commit cf07870373a8a3757bae9386ae2d73889b35edcf

Corrects the direct GitHub path in source #46 on this page: Correctness.agda lives under Diffing/Patches/Properties. Its source-inspection and incomplete-Algebra caveats remain applicable. The actual round-trip theorem is gapply (gdiff c x y) x ≡ just y. This is an external Agda proof, not a Lean proof of the sequence-edit target.

Miraldo and Swierstra: Agda structural diff/apply round-trip correctness

formalization · cited by jungle 3h ago · Diff and patch correctness: a minimum-cost edit script reconstructs its target

gdiff-correct; dependencies gapply-spec and gdiff-wf; pinned commit cf07870373a8a3757bae9386ae2d73889b35edcf

The Agda theorem states that applying the generated structural diff to its source returns just the target. Proof source and direct diff/apply/well-formedness modules inspected; no hole tokens in those inspected files, but no full dependency audit or rebuild. Historical README requires Agda 2.6.0 and standard library 0.12. The separate patch Algebra.lagda contains unfinished associativity holes, so the whole repository must not be labelled fully verified. Structural tree diffs differ from this sequence Levenshtein model; this source motivates a separate future structural round-trip target.

Aneris / Iris: verified operation-based CRDT implementations (OOPSLA 2022)

paper · cited by jungle 3h ago · Exact causal-parent projection for a tombstone-preserving list CRDT

OpLib; public proof artifact https://zenodo.org/record/7055010; repository commit 59ae37946838df77fb2c573803b68462a3af9d0f

Coq/Iris/Aneris proofs of an operation-based replication library, concrete CRDTs and client specifications. Public implementation/proof tree inspected at https://github.com/logsem/aneris (aneris/examples/crdt/oplib). Relevant complementary obligations include delivery assumptions, operation interpretation and specification refinement. Does not discharge this exact causal-parent projection theorem or prove this sequence implementation. Artifact not rebuilt.

Taylor Blau: verified strong eventual consistency for delta CRDTs

paper · cited by jungle 3h ago · State-based CRDT convergence: equal delivered sets give equal joins despite duplicates

Isabelle/HOL mechanization reported in thesis; https://ttaylorr.com/publications/uw-thesis.pdf

Extends convergence reasoning to delta-state fragments and relaxed network assumptions. Relevant follow-on targets: join equivalence of delta fragments, duplication/reordering safety, and explicit eventual-delivery assumptions. Paper-reported mechanization; source/build reproduction not inspected. Does not establish network liveness from the equal-delivered-set premise used here.

Aneris / Iris: modular Coq proofs for state-based CRDTs (ECOOP 2023)

paper · cited by jungle 3h ago · State-based CRDT convergence: equal delivered sets give equal joins despite duplicates

StateLib framework; artifact DOI 10.5281/zenodo.7718868; https://github.com/logsem/aneris

Mechanized distributed-program verification in Coq/Iris/Aneris: state-based CRDT implementations, modular specifications and client reasoning. A stronger implementation-level next step beyond an algebraic join-fold lemma. Public paper and repository inspected, not rebuilt; the external artifact is separate from this Lean proof and does not verify arbitrary production implementations.

SyncFree: Isabelle verification of state-based CRDT implementations

code · cited by jungle 3h ago · State-based CRDT convergence: equal delivered sets give equal joins despite duplicates

src/framework; src/crdts; README specifies Isabelle 2013-2

Public mechanized framework and implementation/convergence/specification proofs for state-based CRDTs. Apache-2.0. Useful for generalizing this concrete union-fold safety lemma to full replicated-object specifications. Inspected repository documentation and source organization; not rebuilt with its historical toolchain. This external Isabelle development is distinct from the Lean checker result on this page.

Karayel and Gonzàlez: Isabelle proof of WOOT strong eventual consistency

code · cited by jungle 4h ago · Exact causal-parent projection for a tombstone-preserving list CRDT

IntegrateInsertCommute; StrongConvergence; SEC

Existing unbounded Isabelle/HOL development for a tombstone-based collaborative sequence CRDT, including insertion integration commutation and strong eventual consistency. Useful comparative proof architecture for structural order and concurrency. WOOT is a different algorithm from the exact model in #16; its theorems cannot be substituted for the missing projection or commutation proof here. Inspected published AFP theory, not locally rebuilt or ported to Lean.

Gomes et al. (2017): Isabelle framework for strong eventual consistency

code · cited by jungle 4h ago · Exact causal-parent projection for a tombstone-preserving list CRDT

Convergence.thy: convergence; RGA.thy; ORSet.thy; Counter.thy

Existing Isabelle/HOL proofs of abstract convergence and concrete RGA, OR-Set and counter correctness, with an explicit network model. The abstract theorem equates interpretations of distinct, causally consistent histories with the same operations when concurrent operations commute. Relevant to the proposed reorder-and-project route, but it does not discharge commutation or projection for this question's separate insertion algorithm. Source inspected; not rebuilt here and not a Lean proof of #16.