diff --git a/Cargo.toml b/Cargo.toml
index 0ba429a1..184b75b3 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -41,6 +41,23 @@ missing_panics_doc = "allow"
 module_name_repetitions = "allow"
 must_use_candidate = "allow"
 
+[workspace.lints.rustdoc]
+# Doc-link rot has no other discoverer: clippy does not read intra-doc
+# links, `cargo test` does not, and nothing else builds docs. A `[`Foo`]`
+# pointing at a renamed, moved or deleted item renders as plain text and
+# misleads the next reader — worse than no link, since it names something
+# and so sends them looking.
+#
+# Here rather than in `RUSTDOCFLAGS` on the CI check, so a plain local
+# `cargo doc` fails the same way CI does. A gate you only meet in CI is a
+# gate you meet too late.
+broken_intra_doc_links = "deny"
+private_intra_doc_links = "deny"
+invalid_html_tags = "deny"
+redundant_explicit_links = "deny"
+bare_urls = "deny"
+unescaped_backticks = "deny"
+
 [workspace.dependencies]
 anyhow = "1"
 libc = "0.2"
diff --git a/nix/checks.nix b/nix/checks.nix
index 56a1a935..7181e8f7 100644
--- a/nix/checks.nix
+++ b/nix/checks.nix
@@ -97,18 +97,12 @@ in
     pname = "hyperhive-workspace";
     version = "0.1.0";
     cargoDocExtraArgs = "--workspace --no-deps --document-private-items";
-    # Every rustdoc lint that catches a *wrong* doc, denied. Kept as an
-    # explicit list rather than a blanket `-D warnings` so that adding a
-    # new rustdoc lint upstream can't silently red the build on a class
-    # nobody has triaged yet.
-    RUSTDOCFLAGS = builtins.concatStringsSep " " [
-      "-D rustdoc::broken_intra_doc_links"
-      "-D rustdoc::private_intra_doc_links"
-      "-D rustdoc::invalid_html_tags"
-      "-D rustdoc::redundant_explicit_links"
-      "-D rustdoc::bare_urls"
-      "-D rustdoc::unescaped_backticks"
-    ];
+    # The lints themselves are NOT set here — they live in
+    # `[workspace.lints.rustdoc]` in the root Cargo.toml, alongside the
+    # clippy table, and every crate inherits them via `[lints] workspace
+    # = true`. That way a plain local `cargo doc` fails exactly the way
+    # this check does; setting them as `RUSTDOCFLAGS` here would make CI
+    # the only place the gate exists.
   };
 
   # Nix options docs evaluation. Cheap: pulls in `nixosOptionsDoc` +