diff --git a/scripts/README.md b/scripts/README.md
index 3c2214c5..867b3d82 100644
--- a/scripts/README.md
+++ b/scripts/README.md
@@ -51,6 +51,44 @@ layout rules re-derived rather than imported, and checks the Reed–Solomon
 syndromes. The encoder was additionally verified against macOS CoreImage's
 decoder for every payload length from 1 to 134 bytes.
 
+## Checks
+
+### check-changelog-registration.sh
+
+Asserts that every file in `src/docs-changelog/` is registered in all the places
+a reader depends on. Runs from `checks.sh` (and so in CI on every PR) before
+`npm ci`, because it needs nothing installed and should fail fast.
+
+Publishing a changelog entry touches four places. A missing file or import breaks
+the build, but **a missing `rawEntries` member or sidebar id still builds, still
+serves the page and still passes lint** — the entry just never shows up where
+people look. That silent success is what this catches:
+
+| Place | Cost of skipping it |
+| --- | --- |
+| `src/docs-changelog/<month>/<entry>.md` | the content itself |
+| `changelogEntries.js` — the `import` | nothing renders it |
+| `changelogEntries.js` — `rawEntries` | absent from the `/changelog` feed |
+| `sidebars-changelog.js` | unreachable from the nav |
+
+The `rawEntries` half is the quietest of the four: an import with no member is
+an _unused import_, which is not an error, so every check passes and the entry
+is simply invisible.
+
+It also checks the reverse — a registry entry with no file behind it — and it
+**fails if its own parsing finds nothing**, so a future change to the file
+layout cannot quietly turn it into a no-op that reports success forever.
+
+`index.mdx` and `latest.mdx` are exempt: they live under `docs-changelog/`
+without being entries. Registrations disabled with a `/* ... */` block comment
+still read as active — the guard is text matching, not a JS parser.
+
+**Usage:**
+
+```bash
+./scripts/check-changelog-registration.sh
+```
+
 ## Field Notes thumbnails
 
 ### thumbnails.sh
diff --git a/scripts/check-changelog-registration.sh b/scripts/check-changelog-registration.sh
new file mode 100755
index 00000000..af60b393
--- /dev/null
+++ b/scripts/check-changelog-registration.sh
@@ -0,0 +1,139 @@
+#!/bin/bash
+#
+# Assert that every changelog entry is registered everywhere it has to be.
+#
+# Publishing an entry means touching four places. A missing file or import
+# breaks the build, but a missing rawEntries member or sidebar id still builds,
+# still serves the page and still passes lint — the entry just never appears
+# where readers look for it. That is the whole reason this check exists: the
+# failure mode is a silent success, so only an assertion catches it.
+#
+# The four places, and what skipping each one costs:
+#
+#   1. src/docs-changelog/<month>/<entry>.md      the content itself
+#   2. changelogEntries.js  `import`              nothing renders it
+#   3. changelogEntries.js  `rawEntries`          absent from the /changelog feed
+#      (an import with no rawEntries member is the quietest failure of the four:
+#      an unused import is not an error, so everything passes and the entry is
+#      simply invisible)
+#   4. sidebars-changelog.js                      unreachable from the nav
+#
+# Checks run in both directions: a file missing from a registry, and a registry
+# entry with no file behind it.
+
+set -euo pipefail
+
+# `join` requires its inputs collated the same way they were sorted, and the
+# runner's locale is not ours to assume.
+export LC_ALL=C
+
+cd "$(dirname "$0")/.."
+
+CONTENT_DIR="src/docs-changelog"
+ENTRIES="src/src/components/ChangelogInfiniteScroll/changelogEntries.js"
+SIDEBAR="src/sidebars-changelog.js"
+
+# Pages that live under docs-changelog/ without being changelog entries: the
+# index, and the /changelog/latest target that the release process repoints.
+NOT_AN_ENTRY=("index" "latest")
+
+for f in "$ENTRIES" "$SIDEBAR"; do
+  [ -f "$f" ] || { echo "error: $f is missing — this check needs updating." >&2; exit 1; }
+done
+
+work=$(mktemp -d)
+trap 'rm -rf "$work"' EXIT
+
+# ── 1 · the content files, month/name with the extension stripped ────────────
+find "$CONTENT_DIR" -type f \( -name '*.md' -o -name '*.mdx' \) \
+  | sed -e "s|^$CONTENT_DIR/||" -e 's/\.mdx\{0,1\}$//' \
+  | sort > "$work/files.all"
+
+# Drop the non-entry pages. The match is anchored on the whole relative path,
+# so it only ever drops root-level index/latest — a month/index.md would still
+# be checked like any other entry.
+cp "$work/files.all" "$work/files"
+for skip in "${NOT_AN_ENTRY[@]}"; do
+  grep -v "^${skip}$" "$work/files" > "$work/files.tmp" || true
+  mv "$work/files.tmp" "$work/files"
+done
+
+# ── 2 · imports: IDENT -> month/name ────────────────────────────────────────
+sed -n "s|^import \([A-Za-z0-9_]*\) from '.*docs-changelog/\(.*\)\.mdx\{0,1\}'.*|\1 \2|p" \
+  "$ENTRIES" | sort > "$work/imports.pairs"
+cut -d' ' -f2 "$work/imports.pairs" | sort > "$work/imported"
+
+# ── 3 · rawEntries: the Component each member renders ───────────────────────
+sed -n 's|^ *Component: \([A-Za-z0-9_]*\),.*|\1|p' "$ENTRIES" | sort -u > "$work/components"
+
+# Translate those identifiers back into paths, so the diff below reads in the
+# same terms as everything else. Options before the operands — BSD join rejects
+# them afterwards — and no error suppression here: a guard that hides its own
+# failures is how this rots into a no-op.
+join -o 2.2 "$work/components" "$work/imports.pairs" | sort > "$work/in_feed"
+
+# ── 4 · sidebar ids ─────────────────────────────────────────────────────────
+# Drop line comments first: the parsers above anchor at ^ and so ignore them
+# already. Block comments are not handled. `|| true` hands a no-match result to
+# the zero-row check below, which reports it — without it grep's exit 1 trips
+# `set -e` here and the script dies with no message at all.
+grep -v '^[[:space:]]*//' "$SIDEBAR" \
+  | grep -oE "'[a-z]+-[0-9]{4}/[^']+'" | tr -d "'" | sort -u > "$work/in_sidebar" || true
+
+# ── the guard has to fail when its own parsing breaks ───────────────────────
+# A regex that quietly matches nothing would turn this whole script into a
+# no-op that reports success forever, which is worse than not having it.
+for pair in "files:$work/files" "imports:$work/imported" \
+            "rawEntries:$work/components" "sidebar:$work/in_sidebar"; do
+  name=${pair%%:*}
+  path=${pair#*:}
+  if [ ! -s "$path" ]; then
+    echo "error: parsed zero $name entries — the file layout changed and this" >&2
+    echo "       check is no longer looking at the right thing. Fix the check." >&2
+    exit 1
+  fi
+done
+
+status=0
+
+report() {
+  local title=$1 fix=$2 list=$3
+  [ -s "$list" ] || return 0
+  status=1
+  echo "error: $title" >&2
+  sed 's/^/  - /' "$list" >&2
+  echo "       $fix" >&2
+  echo >&2
+}
+
+comm -23 "$work/files" "$work/imported"   > "$work/missing_import"
+comm -23 "$work/files" "$work/in_feed"    > "$work/missing_feed"
+comm -23 "$work/files" "$work/in_sidebar" > "$work/missing_sidebar"
+comm -13 "$work/files" "$work/in_sidebar" > "$work/orphan_sidebar"
+comm -13 "$work/files.all" "$work/imported" > "$work/orphan_import"
+
+report "changelog entries are not imported in changelogEntries.js:" \
+       "Add an import for each, newest-first." "$work/missing_import"
+
+report "changelog entries are imported but missing from rawEntries:" \
+       "Add a rawEntries member for each — without one it never reaches the feed." \
+       "$work/missing_feed"
+
+report "changelog entries are missing from sidebars-changelog.js:" \
+       "Add each to its month's category items." "$work/missing_sidebar"
+
+report "sidebars-changelog.js references entries that do not exist:" \
+       "Remove them, or restore the files." "$work/orphan_sidebar"
+
+report "changelogEntries.js imports files that do not exist:" \
+       "Remove the imports, or restore the files." "$work/orphan_import"
+
+if [ "$status" -ne 0 ]; then
+  echo "Publishing a changelog entry means registering it in all of:" >&2
+  echo "  $CONTENT_DIR/<month>/<entry>.md" >&2
+  echo "  $ENTRIES  (both the import and rawEntries)" >&2
+  echo "  $SIDEBAR" >&2
+  exit 1
+fi
+
+echo "changelog registration: $(wc -l < "$work/files" | tr -d ' ') entries, all registered"
diff --git a/scripts/checks.sh b/scripts/checks.sh
index fcf0ea0c..d394dd0b 100755
--- a/scripts/checks.sh
+++ b/scripts/checks.sh
@@ -2,6 +2,10 @@
 
 set -e
 
+# Cheap and dependency-free, so it runs before the install and reports a missing
+# changelog registration in seconds rather than after a full build.
+"$(dirname "$0")/check-changelog-registration.sh"
+
 cd src
 
 npm ci