diff --git a/.github/workflows/standards-build.yml b/.github/workflows/standards-build.yml
index f3ec8bd85..e61c899b1 100644
--- a/.github/workflows/standards-build.yml
+++ b/.github/workflows/standards-build.yml
@@ -82,7 +82,7 @@ jobs:
           # failing for no apparent reason, check `df -h /mnt/lima-colima-txarm`
           # on the txarm VM before suspecting the code: a full cache volume
           # fails whatever happens to be building, not whatever changed.
-          - { name: jouleclaw-rs,     dir: jouleclaw/jouleclaw-rs,                runner: linux-arm64, rustflags: "-C target-feature=+fp16" }
+          - { name: jouleclaw-rs,     dir: jouleclaw/jouleclaw-rs,                runner: linux-arm64, rustflags: "-C target-feature=+fp16", cache_suffix: "-nodebug" }
     steps:
       - uses: actions/checkout@v5
 
@@ -124,6 +124,24 @@ jobs:
             curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --profile minimal
           echo "$HOME/.cargo/bin" >> "$GITHUB_PATH"
 
+      # jouleclaw-rs is the CAPACITY entry above. Linux embeds full DWARF in every
+      # test binary, so with default debuginfo its aarch64 test target outgrows
+      # the ~15 GB left on the shared txarm volume and the link fails with
+      # "No space left on device" (reproduced with the same toolchain, flags and
+      # image). Without debuginfo the same target is ~6 GB and the whole suite
+      # passes. Panic messages keep their file:line: that comes from the panic
+      # location, not from DWARF.
+      #
+      # Set through $GITHUB_ENV rather than a matrix field on purpose: a matrix
+      # field would hand every other job CARGO_PROFILE_DEV_DEBUG="", which cargo
+      # can reject. `cache_suffix` gives this job a fresh cache namespace so it
+      # cannot restore a full-debuginfo target and hold both builds at once;
+      # for every other job the suffix is empty and its key string is unchanged.
+      - name: Trim debuginfo (arm64 jouleclaw)
+        if: matrix.name == 'jouleclaw-rs'
+        shell: bash
+        run: echo "CARGO_PROFILE_DEV_DEBUG=0" >> "$GITHUB_ENV"
+
       - name: Cache cargo registry + target
         uses: actions/cache@v4
         with:
@@ -131,9 +149,9 @@ jobs:
             ~/.cargo/registry
             ~/.cargo/git
             ${{ matrix.dir }}/target
-          key: standards-${{ matrix.name }}-${{ hashFiles(format('{0}/Cargo.lock', matrix.dir), 'rust-toolchain.toml') }}
+          key: standards-${{ matrix.name }}${{ matrix.cache_suffix }}-${{ hashFiles(format('{0}/Cargo.lock', matrix.dir), 'rust-toolchain.toml') }}
           restore-keys: |
-            standards-${{ matrix.name }}-
+            standards-${{ matrix.name }}${{ matrix.cache_suffix }}-
 
       # --all-targets is load-bearing: a plain `cargo check` does not build test
       # targets, and smart-byte's dev-dependencies drifted independently of its