diff --git a/.github/workflows/burrito-release.yaml b/.github/workflows/burrito-release.yaml
index e2fc373..5b9cd90 100644
--- a/.github/workflows/burrito-release.yaml
+++ b/.github/workflows/burrito-release.yaml
@@ -34,6 +34,12 @@ jobs:
         with:
           otp-version: "29.0.3"
           elixir-version: "1.20.3"
+          # Without this, setup-beam's problem matchers promote every
+          # compiler warning from deps (e.g. postgrex/rewrite's deprecated
+          # `xref: [exclude: ...]`, yamerl's deprecated `catch ...` syntax -
+          # both already at their latest published Hex versions, so not
+          # fixable from here) into noisy GH Actions annotations. See #9.
+          disable_problem_matchers: true
       -
         # Version pinned to what Burrito 1.6.0 actually requires - its own
         # README says 0.15.2, but the version check enforces 0.16.0. See
@@ -67,6 +73,12 @@ jobs:
         with:
           otp-version: "29.0.3"
           elixir-version: "1.20.3"
+          # Without this, setup-beam's problem matchers promote every
+          # compiler warning from deps (e.g. postgrex/rewrite's deprecated
+          # `xref: [exclude: ...]`, yamerl's deprecated `catch ...` syntax -
+          # both already at their latest published Hex versions, so not
+          # fixable from here) into noisy GH Actions annotations. See #9.
+          disable_problem_matchers: true
       -
         # Same Burrito build as the `burrito` job above, so it needs the same
         # pinned Zig (see that job's comment) - missing here would fail this
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 5be5481..d90d635 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -21,6 +21,12 @@ jobs:
         with:
           otp-version: "29.0.3"
           elixir-version: "1.20.3"
+          # Without this, setup-beam's problem matchers promote every
+          # compiler warning from deps (e.g. postgrex/rewrite's deprecated
+          # `xref: [exclude: ...]`, yamerl's deprecated `catch ...` syntax -
+          # both already at their latest published Hex versions, so not
+          # fixable from here) into noisy GH Actions annotations. See #9.
+          disable_problem_matchers: true
       -
         name: Cache deps/build
         uses: actions/cache@v6