diff --git a/docs/ops/HYPERTWIST_REPOSITORY_HYGIENE_AND_PUBLIC_SURFACE_SYNC_POLICY_2026-08-31.md b/docs/ops/HYPERTWIST_REPOSITORY_HYGIENE_AND_PUBLIC_SURFACE_SYNC_POLICY_2026-08-31.md
new file mode 100644
index 0000000..e16b307
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+++ b/docs/ops/HYPERTWIST_REPOSITORY_HYGIENE_AND_PUBLIC_SURFACE_SYNC_POLICY_2026-08-31.md
@@ -0,0 +1,57 @@
+# HyperTwist Repository Hygiene And Public Surface Sync Policy
+
+**Date:** 2026-08-31
+**Status:** Active
+**Scope:** Native runtime, browser shell, public website, documentation,
+validation, packaging, and release packets.
+
+## Relationship to existing doctrine
+
+`HYPERTWIST_PACKET_CLEANUP_AND_REBUILDABLE_ARTIFACT_HYGIENE_2026-05-20.md`
+continues to govern protected and rebuildable artifact classes. This policy
+adds immediate cleanup cadence and mandatory synchronization of public product
+truth.
+
+## Hygiene cadence
+
+Capture `git status --short` before work. Classify packet-owned output before
+running generators, Unreal builds, tests, website builds, analyzers, extraction,
+or packaging. Once a run has yielded the evidence needed by the packet, remove
+its disposable output immediately: temporary Unreal build/automation products,
+web build and coverage output, analyzer mirrors, test reports, caches, logs,
+screenshots, temporary package roots, and other clearly rebuildable residue
+created by that run.
+
+Use project cleanup scripts and preserve all evidence required by the canonical
+Windows Unreal gate. Never delete accepted packages/evidence, committed runtime
+assets, custody mirrors, user data, credentials, unrelated dirt, or ambiguous
+operator files. Do not convert residue into permanent ignored state merely to
+make status appear clean. Capture final status and explain retained artifacts.
+
+## Capability-documentation synchronization
+
+Every user-visible capability addition, removal, rename, gating change, or
+material behavior change must update all applicable surfaces in the same
+packet:
+
+- `docs/v6_5_deep_manual_pack/HyperTwist/FEATURE_REGISTRY.md` and current
+  roadmap/release authorities;
+- native and browser operator manuals, onboarding, help, and in-product copy;
+- homepage/public feature cards, capabilities, pricing comparison, Help Center,
+  Docs/About/resources/support pages;
+- affected architecture/development docs and codemaps;
+- the current-version changelog or release-notes entry.
+
+The public website and native simulator must retain their documented ownership
+boundary. Changelog maintenance is mandatory and additive, but it never
+substitutes for feature, pricing, help, or manual synchronization. Historical
+entries remain intact, and candidate source is not released until its package
+and deployment evidence exists.
+
+## Completion gate
+
+Run the mandatory Windows Unreal build for a logical C++ slice, plus applicable
+website, docs, and package checks. Search current authorities for stale claims,
+verify generated public/manual outputs against canonical source, clean
+packet-owned residue, and record final status. If an applicable surface needs
+no edit, state that it was reviewed and why.
diff --git a/docs/v6_5_deep_manual_pack/HyperTwist/DEVELOPMENT.md b/docs/v6_5_deep_manual_pack/HyperTwist/DEVELOPMENT.md
index 6fb5d73..7ed1a77 100644
--- a/docs/v6_5_deep_manual_pack/HyperTwist/DEVELOPMENT.md
+++ b/docs/v6_5_deep_manual_pack/HyperTwist/DEVELOPMENT.md
@@ -36,6 +36,16 @@ claims over the same capability.
   training behavior, replay/coaching execution, higher-dimensional runtime
   families, and the current serious control/runtime evidence
 
+## Repository hygiene and public truth
+
+Every packet follows
+`docs/ops/HYPERTWIST_REPOSITORY_HYGIENE_AND_PUBLIC_SURFACE_SYNC_POLICY_2026-08-31.md`.
+Clean packet-created build/test residue immediately after retaining the evidence
+it produced. Every user-visible change must also reconcile the feature registry,
+native/browser manuals and help, homepage and other public feature surfaces,
+pricing comparison where applicable, current roadmap/release authority, and the
+current-version changelog. A changelog entry alone is not documentation sync.
+
 ## Refactor toolchain
 
 HyperTwist now has its own bounded refactor/analyzer entry points: