diff --git a/.claude/CLAUDE.md b/.claude/CLAUDE.md
index ed0178fb..5de41670 100644
--- a/.claude/CLAUDE.md
+++ b/.claude/CLAUDE.md
@@ -61,15 +61,23 @@ npm run dev:backend
 # Docker
 npm run docker:dev
 
-# Verify a change before declaring it done (mirrors CI: frontend lint + typecheck)
+# Verify a change before declaring it done (mirrors CI: lint + typecheck + build)
 npm run verify
 ```
 
 **Before declaring any change done, run `npm run verify`.** It runs the same
-hermetic gates as CI (`.github/workflows/ci.yml`: frontend lint + typecheck), so
-green locally means green on `main`. Build and the full-stack Playwright e2e are
-not yet gated in CI (build hits a prisma-engine issue; e2e needs both servers +
-a DB) — run those manually until wired.
+hermetic gates as CI (`.github/workflows/ci.yml`: frontend lint + typecheck +
+build), so green locally means green on `main`.
+
+The build is in the gate deliberately. It used to be deferred, and that gap has
+a receipt: contentlayer 0.3.1 reaches into a React internal that React 19
+removed, so `/blog/[slug]` threw `d.getOwner is not a function` during prerender
+and production sat on a stale build for weeks. Lint and typecheck were green the
+whole time — only a build could have caught it.
+
+Note: the build needs Node 18 (`.nvmrc`); contentlayer crashes on exit under
+Node 20+. The full-stack Playwright e2e is still not gated — it needs both
+servers plus a seeded DB, so run it manually until that is wired.
 
 ---
 
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 68cc5ed6..a0a86084 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -41,15 +41,18 @@ jobs:
         run: npm ci --legacy-peer-deps
 
       # SSOT: one definition of "verified" lives in the ROOT package.json
-      # `verify` (frontend lint + typecheck), run identically here and locally.
-      # Runs from repo root — the script cds into frontend itself.
+      # `verify` (lint + typecheck + build), run identically here and locally.
+      # Runs from repo root — the scripts cd into frontend themselves.
+      #
+      # Build is IN the gate as of 2026-08-04. It was deferred on a prisma-engine
+      # issue, and the cost of that gap was exact: contentlayer 0.3.1 reaches into
+      # a React internal that React 19 removed, so `/blog/[slug]` threw
+      # "d.getOwner is not a function" during prerender. lint and typecheck were
+      # both green — only a build could have caught it. The breakage sat on main
+      # while every CI run reported success.
       - name: Verify
         run: npm run verify
 
-      # Build is DEFERRED, not skipped silently. `prisma generate` currently
-      # fails in CI on a missing engine (query_engine_bg.postgresql.wasm) — a
-      # repo tooling issue to fix separately, not a gate-worthy signal. The
-      # full-stack Playwright e2e is also deferred (needs both servers + a DB).
-      # This floor gates the frontend signals that never ran before:
-      # lint + typecheck. Add build + e2e once the prisma engine is resolved
-      # (revampit e2e-local pattern in dotfiles/templates/ci/README.md).
+      # The full-stack Playwright e2e is still DEFERRED, not skipped silently:
+      # it needs both servers plus a seeded DB (lift revampit's e2e-local pattern
+      # from dotfiles/templates/ci/README.md once that is wired).
diff --git a/package.json b/package.json
index 9dbddee4..ef757119 100644
--- a/package.json
+++ b/package.json
@@ -25,7 +25,8 @@
     "test:debug": "npx playwright test --debug",
     "test:headed": "npx playwright test --headed",
     "test:report": "npx playwright show-report",
-    "verify": "npm run lint && cd frontend && npx tsc --noEmit"
+    "typecheck": "cd frontend && npx tsc --noEmit",
+    "verify": "npm run lint && npm run typecheck && npm run build"
   },
   "keywords": [
     "data-capture",