diff --git a/__tests__/ci.test.js b/__tests__/ci.test.js
index fcde6b5..208402a 100644
--- a/__tests__/ci.test.js
+++ b/__tests__/ci.test.js
@@ -15,10 +15,13 @@ const dockerfile = fs.readFileSync(path.join(ROOT, "Dockerfile"), "utf-8");
 
 // Comment lines stripped, so an explanation that quotes a key cannot satisfy
 // (or break) a pin.
-const ciCode = ci
-  .split("\n")
-  .filter((line) => !/^\s*#/.test(line))
-  .join("\n");
+function stripCommentLines(text) {
+  return text
+    .split("\n")
+    .filter((line) => !/^\s*#/.test(line))
+    .join("\n");
+}
+const ciCode = stripCommentLines(ci);
 
 // Lines of a top-level-indented block (`  pull_request:`), up to the next key at
 // the same or a lower indentation.
@@ -77,10 +80,32 @@ describe("CI workflow", () => {
       if (/^\s*uses:|\n\s*uses:/.test(step)) expect(step).not.toMatch(/working-directory:/);
     }
   });
+
+  // `continue-on-error: true` turns a red step green without a trace in the
+  // commit status. Any spelling of the key counts: a block key or a list item,
+  // but also a flow mapping and a quoted key, which a pin anchored at the start
+  // of the line let through (#35). Unanchored on purpose: the key quoted in a
+  // `run:` script, a step name or a trailing comment fails the pin too, loudly.
+  // Only full comment lines are exempt, being stripped from `ciCode`.
+  const CONTINUE_ON_ERROR = /continue-on-error["']?\s*:/;
+
   test("never lets a failing step pass", () => {
-    // `continue-on-error: true` turns a red step green without a trace in the
-    // commit status. Anchored on the key position, so only a real key counts.
-    expect(ciCode).not.toMatch(/^\s*(- )?continue-on-error\s*:/m);
+    expect(ciCode).not.toMatch(CONTINUE_ON_ERROR);
+  });
+
+  // The detector itself, through the same comment stripping as `ciCode`. Anchor
+  // it at the start of the line again and the last two spellings turn red.
+  test.each([
+    ["a block key", "      - name: x\n        run: npm test\n        continue-on-error: true"],
+    ["a list item", "      - continue-on-error: true\n        run: npm test"],
+    ["a flow mapping", "      - { name: x, run: false, continue-on-error: true }"],
+    ["a quoted key", '      - name: x\n        "continue-on-error": true'],
+  ])("the continue-on-error pin catches %s", (_, step) => {
+    expect(stripCommentLines(step)).toMatch(CONTINUE_ON_ERROR);
+  });
+
+  test("the continue-on-error pin ignores a full comment line quoting the key", () => {
+    expect(stripCommentLines("      # never add continue-on-error: true here")).not.toMatch(CONTINUE_ON_ERROR);
   });
 });