diff --git a/.github/workflows/standards-build.yml b/.github/workflows/standards-build.yml
index 8a13bc820..f3ec8bd85 100644
--- a/.github/workflows/standards-build.yml
+++ b/.github/workflows/standards-build.yml
@@ -50,18 +50,18 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - { name: jcp-rs,           dir: jcp/jcp-rs,                            runner: linux }
-          - { name: sandbox-rs,       dir: sandbox/sandbox-rs,                    runner: linux }
+          - { name: jcp-rs,           dir: jcp/jcp-rs,                            runner: linux, conformance: jcp-conformance }
+          - { name: sandbox-rs,       dir: sandbox/sandbox-rs,                    runner: linux, conformance: sandbox-conformance }
           - { name: smart-byte-rs,    dir: smart-byte/smart-byte-rs,              runner: linux }
           - { name: openpay,          dir: openpay,                               runner: linux-arm64 }
           - { name: joule-code-rs,    dir: joule-code/joule-code-rs,              runner: linux-arm64 }
-          - { name: map-rs,           dir: map/map-rs,                            runner: linux-arm64 }
-          - { name: aac-rs,           dir: aac/aac-rs,                            runner: linux-arm64 }
+          - { name: map-rs,           dir: map/map-rs,                            runner: linux-arm64, conformance: map-conformance }
+          - { name: aac-rs,           dir: aac/aac-rs,                            runner: linux-arm64, conformance: aac-conformance }
           - { name: joulecontract-rs, dir: joulecontract/joulecontract-rs,        runner: linux-arm64, z3: true }
           - { name: jouledesk-rs,     dir: jouledesk/jouledesk-rs,                runner: macos }
           - { name: arl-rs,           dir: arl/arl-rs,                            runner: macos }
           - { name: sense-rs,         dir: sense/sense-rs,                        runner: macos }
-          - { name: proof-rs,         dir: proof/proof-rs,                        runner: linux, z3: true }
+          - { name: proof-rs,         dir: proof/proof-rs,                        runner: linux, z3: true, conformance: proof-conformance }
           - { name: joulehook-rs,     dir: joulehook/joulehook-rs,                runner: macos }
           - { name: eoc-rs,           dir: eoc/eoc-rs,                            runner: linux }
           - { name: mesh-rs,          dir: mesh/mesh-rs,                          runner: linux-arm64 }
@@ -150,3 +150,32 @@ jobs:
         env:
           RUSTFLAGS: ${{ matrix.rustflags }}
         run: cargo test --workspace
+
+      # Run each standard's conformance suite.
+      #
+      # These suites live in a binary's `main()`, not in `#[test]`, so
+      # `cargo test` never executes them — verified, not assumed:
+      # `cargo test -p aac-conformance` runs **0 tests** while
+      # `cargo run -p aac-conformance` runs **40 checks**; map is 1 test vs 15
+      # checks. Same shape for jcp, proof and sandbox. The suites include
+      # negative vectors (`C-neg`, `Cneg`), which are the ones that catch a
+      # verifier ACCEPTING what it must reject.
+      #
+      # This is the `main()` instance of the same bug as a feature-gated test:
+      # the code compiles under `--all-targets`, reports nothing, and looks
+      # covered. Compiling a suite is not running it.
+      #
+      # `--bin` is explicit because these crates also ship a `gen-vectors`
+      # binary; `cargo run -p <crate>` is ambiguous with two binaries and fails
+      # rather than choosing — which is how this step would silently never run.
+      #
+      # No path argument: these binaries take none. They check the
+      # implementation against in-code expectations, which is a different claim
+      # from validating the published `conformance/v1` files on disk — nothing
+      # in CI does that yet, and this step does not pretend to.
+      - name: Conformance suite
+        if: matrix.conformance
+        working-directory: ${{ matrix.dir }}
+        env:
+          RUSTFLAGS: ${{ matrix.rustflags }}
+        run: cargo run -q -p ${{ matrix.conformance }} --bin ${{ matrix.conformance }}