Branch Archive: Retired Experiment Branches

Created: 2026-07-09 Purpose: Resolve every branch name cited in this repository's scientific ledgers to a durable, permanent Git reference.

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Why this document exists

The scientific ledgers in docs/research/ and docs/optimization/ cite the branch on which each experiment was performed — this is what makes a recorded result reproducible rather than merely asserted. Branch names, however, are mutable local pointers: once a branch is deleted, its name no longer resolves, and a citation such as **Branch**: feat/wallbreaker-freq-split becomes a dangling reference.

On 2026-07-09 the repository's 19 stray feature branches were retired. This table preserves the mapping from every cited branch name to the immutable commit SHA it pointed at, together with the durable reference through which that commit remains reachable. No commit referenced by any ledger was lost.

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Resolution table

A commit is reachable — and therefore permanently safe from garbage collection — if it is an ancestor of master, or if an annotated tag points at it. Every retired branch satisfies one of these two conditions.

Retired branch	Commit	Reachable via	Content status
feat/wallbreaker-freq-split	3d372ef	tag experiment/wallbreaker-freq-split	Unique code, never merged
feat/wallbreaker-substring-opt	4a62248	tag experiment/wallbreaker-substring-opt	Unique docs, superseded
perf/phonetic-normalized-opt-5	9a57cca	tag archive/phonetic-normalized-opt-5	Patch-equivalent to master
release-rebuild-v0.9.0	66de57c	tag archive/release-rebuild-v0.9.0	Patch-equivalent to master
feat/wallbreaker-benchmarks	7543b75	ancestor of master	Merged
feat/wallbreaker-simd	5acf623	ancestor of master	Merged
dylon/ci-sibling-fix	1968089	ancestor of master	Merged
fix-nodup-definition	198b525	ancestor of master	Merged
opt/baseline	845a288	ancestor of master	Merged
opt/llev-h1-intern-class-names	1ec7f71	ancestor of master	Merged
opt/llev-h2-named-class-lookup	5080be7	ancestor of master	Merged
opt/llev-h4-smallvec-charclass	3db880e	ancestor of master	Merged
perf/phonetic-normalized-benchmarks	dd1438c	ancestor of master	Merged
perf/phonetic-normalized-opt-1	62db70d	ancestor of master	Merged
perf/phonetic-normalized-opt-2	ea54db5	ancestor of master	Merged
perf/phonetic-normalized-opt-3	50ceebb	ancestor of master	Merged
perf/phonetic-normalized-opt-4	3418d30	ancestor of master	Merged
perf/phonetic-normalized-opt-6-bktree	316f874	ancestor of master	Merged
proof-multirule-axiom	9fa2fc9	ancestor of master	Merged

Surviving branches: master and release (the latter carries one intentional commit, 32c9613, disabling PathMap in Cargo.toml).

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The two tags that carry unique content

Only two retired branches held anything absent from master. Both are now annotated tags whose messages record the full hypothesis, verdict, and measurements; read them with git show <tag>.

experiment/wallbreaker-freq-split

The sole surviving copy of FrequencyPatternSplitter and FrequencyWallBreaker (≈786 insertions across src/wallbreaker/pattern_splitter.rs, src/wallbreaker/mod.rs, and benches/wallbreaker_benchmarks.rs). It is the evidence behind Experiment 3 of the WallBreaker scientific ledger, whose verdict was ❌ REJECTED (Overall regression).

git show experiment/wallbreaker-freq-split                              # hypothesis, results, analysis
git show experiment/wallbreaker-freq-split:src/wallbreaker/pattern_splitter.rs
git log --oneline master..experiment/wallbreaker-freq-split             # the two unmerged commits

This code must not be deleted: it is the reproducible basis of a documented negative result. It forked 170 commits behind master and predates the migration of the dictionary module to the libdictenstein crate (cd82727), so any attempt to rebase it onto master will conflict in src/dictionary/.

experiment/wallbreaker-substring-opt

Documents the Phase 2 suffix-link substring-search optimization as rejected on the grounds that the then-current SCDAWG was a prefix DAWG rather than a true suffix automaton. This conclusion was subsequently overturned: master implemented precisely that conversion in Experiment 5, "True SCDAWG Implementation (𝒪(∣pattern∣) Substring Search)". The tag is retained as the historical record of the intermediate negative result.

Its source edits touch src/dictionary/scdawg.rs and src/dictionary/scdawg_char.rs, neither of which exists on master any longer (migrated to libdictenstein in cd82727). They must not be cherry-picked.

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Recovering a retired branch

Tags are immutable pointers; recreating a working branch from one is a single command.

git switch -c feat/wallbreaker-freq-split experiment/wallbreaker-freq-split

To confirm nothing has been orphaned:

git fsck --unreachable --no-reflogs | grep commit    # expect no output