diff --git a/.config/nextest.toml b/.config/nextest.toml
new file mode 100644
index 0000000000..c7c5545dc9
--- /dev/null
+++ b/.config/nextest.toml
@@ -0,0 +1,5 @@
+[profile.ci]
+# Do not cancel the test run on the first failure.
+fail-fast = false
+# Terminate test after three slow periods of 60 seconds.
+slow-timeout = { period = "60s", terminate-after = 3 }
diff --git a/.github/workflows/check.yml b/.github/workflows/check.yml
index 1b9c2e8200..d9179bc35e 100644
--- a/.github/workflows/check.yml
+++ b/.github/workflows/check.yml
@@ -17,7 +17,6 @@ on:
 env:
   CARGO_TERM_COLOR: always
   RUST_BACKTRACE: 1
-  DUMP_SIMULATION_SEEDS: /tmp/simulation-seeds
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref_name }}
@@ -86,11 +85,13 @@ jobs:
         env:
           RUST_LOG: trace
         run: |
+          DUMP_SIMULATION_SEEDS="$(pwd)/simulation-seeds"
+          export DUMP_SIMULATION_SEEDS
           # shellcheck disable=SC2086
           if [ "${{ matrix.rust-toolchain }}" == "stable" ]; then
-            cargo +${{ matrix.rust-toolchain }} llvm-cov nextest $BUILD_TYPE --features ci --no-fail-fast --lcov --output-path lcov.info
+            cargo +${{ matrix.rust-toolchain }} llvm-cov nextest $BUILD_TYPE --features ci --profile ci --lcov --output-path lcov.info
           else
-            cargo +${{ matrix.rust-toolchain }} nextest run $BUILD_TYPE --features ci --no-fail-fast
+            cargo +${{ matrix.rust-toolchain }} nextest run $BUILD_TYPE --features ci --profile ci
           fi
 
       - name: Run client/server transfer
@@ -121,11 +122,11 @@ jobs:
         if: matrix.type == 'debug' && matrix.rust-toolchain == 'stable'
 
       - name: Save simulation seeds artifact
-        if: env.DUMP_SIMULATION_SEEDS
+        if: always()
         uses: actions/upload-artifact@b4b15b8c7c6ac21ea08fcf65892d2ee8f75cf882 # v4.4.3
         with:
           name: simulation-seeds-${{ matrix.os }}-${{ matrix.rust-toolchain }}-${{ matrix.type }}
-          path: ${{ env.DUMP_SIMULATION_SEEDS }}
+          path: simulation-seeds
           compression-level: 9
 
   bench:
diff --git a/.github/workflows/sanitize.yml b/.github/workflows/sanitize.yml
index 4d6bef060a..2862a221e5 100644
--- a/.github/workflows/sanitize.yml
+++ b/.github/workflows/sanitize.yml
@@ -76,7 +76,7 @@ jobs:
             PWD=$(pwd)
             export LSAN_OPTIONS="suppressions=$PWD/suppressions.txt"
           fi
-          cargo nextest run -Z build-std --features ci --target "$TARGET"
+          cargo nextest run -Z build-std --features ci --profile ci --target "$TARGET"
 
       - name: Save simulation seeds artifact
         if: env.DUMP_SIMULATION_SEEDS