diff --git a/.github/workflows/no-js-scan.yml b/.github/workflows/no-js-scan.yml
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+# SPDX-License-Identifier: MPL-2.0
+name: No-JS Scan (warn-first)
+
+# Estate policy: no hand-authored JavaScript/TypeScript source
+# (see standards docs/NO-JAVASCRIPT-SOURCE-POLICY.adoc). This workflow is
+# WARN-FIRST: it reports the authored-JS surface for migration but never fails
+# the build. The authoritative hard-block for NEW JS in non-carve-out paths is
+# hypatia (cicd_rules/javascript_detected); this is an additive companion.
+
+on:
+  push:
+    paths:
+      - '**/*.js'
+      - '**/*.jsx'
+      - '**/*.mjs'
+      - '**/*.cjs'
+      - '**/*.ts'
+      - '**/*.tsx'
+  pull_request:
+    paths:
+      - '**/*.js'
+      - '**/*.jsx'
+      - '**/*.mjs'
+      - '**/*.cjs'
+      - '**/*.ts'
+      - '**/*.tsx'
+
+# Estate guardrail: cancel superseded runs (read-only check, no mutation).
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read
+
+jobs:
+  scan-authored-js:
+    name: Scan for hand-authored JavaScript/TypeScript
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v4
+
+      - name: Report authored JS/TS (warn-first, non-blocking)
+        shell: bash
+        run: |
+          # Exclude only things that are NOT hand-authored source: vendored
+          # (node_modules, deps, vendor, .git), generated/compiled (*.res.js,
+          # *.res.mjs, lib/{js,es6,bs}, out, dist, .deno, generated/, *.min.js),
+          # and declaration headers (*.d.ts). Everything else is reported.
+          mapfile -t hits < <(
+            find . \
+              \( -path './.git' -o -name node_modules -o -path '*/deps/*' \
+                 -o -path '*/vendor/*' -o -path '*/lib/js/*' -o -path '*/lib/es6/*' \
+                 -o -path '*/lib/bs/*' -o -path '*/out/*' -o -path '*/dist/*' \
+                 -o -path '*/.deno/*' -o -path '*/generated/*' \) -prune -o \
+              -type f \
+              \( -name '*.js' -o -name '*.jsx' -o -name '*.mjs' -o -name '*.cjs' \
+                 -o -name '*.ts' -o -name '*.tsx' \) \
+              ! -name '*.res.js' ! -name '*.res.mjs' ! -name '*.min.js' ! -name '*.d.ts' \
+              -print 2>/dev/null | sort || true
+          )
+
+          count=${#hits[@]}
+
+          {
+            echo "# No-JS scan (warn-first)"
+            echo
+            echo "Estate policy: **no hand-authored JavaScript/TypeScript source.**"
+            echo "Destination is AffineScript -> typed-wasm, or Rust + Zig -> wasm."
+            echo "This check is **non-blocking** — it reports the migration surface only."
+            echo "Authoritative hard-block for new files: hypatia \`cicd_rules/javascript_detected\`."
+            echo "Policy: standards \`docs/NO-JAVASCRIPT-SOURCE-POLICY.adoc\`."
+            echo
+            echo "**Hand-authored JS/TS files found: ${count}**"
+            if [ "${count}" -gt 0 ]; then
+              echo
+              echo '| # | File |'
+              echo '|---|------|'
+              i=0
+              for f in "${hits[@]}"; do
+                i=$((i + 1))
+                echo "| ${i} | \`${f#./}\` |"
+              done
+            else
+              echo
+              echo "No hand-authored JavaScript/TypeScript found. :white_check_mark:"
+            fi
+          } >> "${GITHUB_STEP_SUMMARY}"
+
+          if [ "${count}" -gt 0 ]; then
+            echo "::warning title=No-JS (warn-first)::${count} hand-authored JS/TS file(s) present. Estate target is AffineScript->typed-wasm / Rust+Zig->wasm. See standards docs/NO-JAVASCRIPT-SOURCE-POLICY.adoc (non-blocking)."
+          fi
+
+          # Warn-first: never fail the build.
+          exit 0
diff --git a/docs/NO-JAVASCRIPT-SOURCE-POLICY.adoc b/docs/NO-JAVASCRIPT-SOURCE-POLICY.adoc
new file mode 100644
index 00000000..25bde700
--- /dev/null
+++ b/docs/NO-JAVASCRIPT-SOURCE-POLICY.adoc
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: MPL-2.0
+= No Hand-Authored JavaScript (Source) Policy
+:revdate: 2026-06-02
+:status: ACTIVE (warn-first rollout)
+:issue-254: hyperpolymath/standards#254
+
+This document is the canonical estate-wide statement that estate-authored code
+MUST NOT contain hand-authored JavaScript or TypeScript *source*. It complements
+rather than replaces the existing machinery:
+
+* `docs/JS-RUNTIME-POLICY.adoc` — the JS *runtime & package-manager* hierarchy
+  (Deno > Bun > pnpm > npm) and the lockfile / `node_modules` rules.
+* `.claude/CLAUDE.md` §JavaScript Exemptions / §TypeScript Exemptions — the
+  human-readable mirror of the hypatia carve-outs.
+* hypatia `cicd_rules/javascript_detected`, `javascript_jsx_detected`,
+  `typescript_detected` — the SINGLE SOURCE OF TRUTH for detection and the
+  `path_allow_prefixes` carve-outs. This document does not override it.
+
+== The rule
+
+Estate-authored application logic is written in AffineScript (compiled to
+typed-wasm) or, for performance / systems / ABI / FFI work, in Rust + Zig
+compiled to WebAssembly with Idris2-proven ABIs. Hand-authored `.js`, `.jsx`,
+`.mjs`, `.cjs`, `.ts`, and `.tsx` source is therefore not an accepted
+destination for new estate code.
+
+This is a deliberate tightening of the earlier "JavaScript banned where
+AffineScript cannot reach" stance ({issue-254}): the target is *no* hand-authored
+JavaScript, not merely *no unnecessary* JavaScript.
+
+== What this does NOT cover (not "JavaScript source")
+
+The following are out of scope and MUST NOT be treated as violations:
+
+* *Generated / compiled output* — `*.res.js`, `*.res.mjs`, `lib/js/**`,
+  `lib/es6/**`, `lib/bs/**`, `out/**`, `dist/**`, `.deno/**`, `generated/**`,
+  `*.min.js`. Compiler output is not source.
+* *The build-time wasm host shim* — the generated wasm-bindgen-class glue that
+  lets a wasm module reach the browser DOM/canvas. It is generated, not authored,
+  and unavoidable in a browser host (wasm has no direct DOM access). "No
+  JavaScript" means no hand-authored application JavaScript.
+* *Declaration headers* — `*.d.ts` (FFI / library type boundaries).
+* *Vendored / upstream* — `node_modules/**`, `deps/**`, and vendored forks.
+* *Documented carve-outs* — every `path_allow_prefixes` entry on the hypatia
+  rules (MCP / plugin hosts, tooling configs, bootstrap shims, consumer-facing
+  bindings, VSCode extension entry points, archived repos, etc.). hypatia is
+  authoritative; the CLAUDE.md tables mirror it.
+
+== Enforcement (two deliberately distinct layers)
+
+[cols="1,3", options="header"]
+|===
+| Layer | Behaviour
+
+| hypatia `cicd_rules/javascript_detected` (authoritative)
+| HARD-BLOCK for NEW `.js` / `.jsx` in non-carve-out paths, with an inline
+  pragma escape (`// hypatia: allow cicd_rules/javascript_detected -- <reason>`).
+  Existing files are grandfathered while the {issue-254} migration proceeds.
+
+| `no-js-scan.yml` (this rollout — WARN-FIRST)
+| NON-BLOCKING companion. On any push / PR touching JS or TS it reports the full
+  count and list of hand-authored JS/TS to the run summary, so each repo's
+  migration surface is visible. It does not fail the build while a repo's surface
+  is non-zero (once a repo reaches zero it flips to a blocking gate, e.g.
+  `gossamer`). It excludes only the
+  generated / vendored / declaration files listed above. By owner decision a
+  repo flips from warn to block once its surface reaches zero.
+|===
+
+== Rollout status (2026-06-02)
+
+* `gossamer` — surface is zero, so `no-js-scan` runs as a **blocking gate**: any
+  newly introduced hand-authored JS/TS fails CI.
+* `standards` (29) and `burble` (14) — **warn-first** (non-blocking) while their
+  surfaces migrate; each flips to blocking once it reaches zero.
+* `paint-type` — joins when write access is available; its `src/ui/app.js` is the
+  increment-0 MVP UI, slated to move into Rust/wasm per that repo's ADR-0002.
+
+Other estate repos adopt via template propagation.