diff --git a/.github/workflows/echidna.yml b/.github/workflows/echidna.yml
new file mode 100644
index 00000000..ba5d31f6
--- /dev/null
+++ b/.github/workflows/echidna.yml
@@ -0,0 +1,65 @@
+name: Echidna
+
+on:
+  pull_request:
+  workflow_dispatch: {}
+
+permissions:
+  contents: read
+
+concurrency:
+  group: echidna-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
+env:
+  NODEJS_VERSION: '20'
+  ECHIDNA_IMAGE: ghcr.io/crytic/echidna/echidna:v2.3.1
+
+jobs:
+  echidna:
+    name: Echidna / ${{ matrix.contract }}
+    runs-on: ubuntu-latest
+    timeout-minutes: 180
+    strategy:
+      fail-fast: false
+      matrix:
+        contract:
+          - EchidnaStakeRegistryHarness
+          - EchidnaPriceOracleHarness
+          - EchidnaPostageStampHarness
+          - EchidnaRedistributionHarness
+          - EchidnaRedistributionClaimHarness
+          - EchidnaSystemHarness
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js and Yarn
+        uses: actions/setup-node@v4
+        with:
+          node-version: ${{ env.NODEJS_VERSION }}
+          cache: yarn
+
+      - name: Install dependencies
+        run: yarn install --frozen-lockfile
+
+      - name: Run Echidna
+        env:
+          ECHIDNA_CONTRACT: ${{ matrix.contract }}
+          # 9000s leaves ~30 min for checkout, yarn, compile, and image pull
+          # inside the 180-minute job cap so a timeout still uploads artifacts.
+          ECHIDNA_TIMEOUT: '9000'
+        run: yarn echidna
+
+      - name: Upload reproducers and logs
+        if: failure()
+        uses: actions/upload-artifact@v4
+        with:
+          name: echidna-${{ matrix.contract }}
+          path: |
+            echidna/logs/
+            echidna/corpus/by-contract/
+            crytic-export/
+          if-no-files-found: warn
+          retention-days: 14
diff --git a/.gitignore b/.gitignore
index 9062f884..26493b77 100644
--- a/.gitignore
+++ b/.gitignore
@@ -42,7 +42,8 @@ tenderly.log
 
 # Echidna fuzzing
 echidna/corpus/
+echidna/logs/
 crytic-export/
 
 # Cursor
-.cursor/rules/audit-code.mdc
\ No newline at end of file
+.cursor/rules/audit-code.mdc
diff --git a/README.md b/README.md
index a53378e5..d0be0008 100644
--- a/README.md
+++ b/README.md
@@ -119,6 +119,8 @@ Harness layout, properties, and troubleshooting are documented in [echidna/READM
 yarn echidna
 ```
 
+CI runs the full Echidna campaign on every pull request. See [echidna/README.md](./echidna/README.md#ci).
+
 ## Run
 
 ### [Tests](./test)
diff --git a/echidna/README.md b/echidna/README.md
index 130bb3f0..27ea447c 100644
--- a/echidna/README.md
+++ b/echidna/README.md
@@ -125,10 +125,26 @@ yarn echidna   # all harnesses; needs Docker
 | `seqLen` | 320 | `ECHIDNA_SEQ_LEN` |
 | `maxBlockDelay` | 152 | — |
 | workers | yaml | `ECHIDNA_WORKERS` |
+| seed | random | `ECHIDNA_SEED` |
+| timeout (seconds) | none | `ECHIDNA_TIMEOUT` |
 
 Single harness: `ECHIDNA_CONTRACT=EchidnaRedistributionHarness yarn echidna` (also: `EchidnaStakeRegistryHarness`, `EchidnaPriceOracleHarness`, `EchidnaPostageStampHarness`, `EchidnaRedistributionClaimHarness`, `EchidnaSystemHarness`).
 
-Config: `echidna/echidna.yaml` (`ECHIDNA_CONFIG` to override). Corpus/coverage: `echidna/corpus/by-contract/<HarnessName>/` (gitignored). Crytic: `crytic-export/`.
+Config: `echidna/echidna.yaml` (`ECHIDNA_CONFIG` to override). Corpus/coverage: `echidna/corpus/by-contract/<HarnessName>/` (gitignored). Logs: `echidna/logs/` (gitignored). Crytic: `crytic-export/`.
+
+## CI
+
+Workflow: [`.github/workflows/echidna.yml`](../.github/workflows/echidna.yml). Runs on every pull request (and manual `workflow_dispatch`).
+
+One matrix job per harness, using the same campaign as local `yarn echidna` (`echidna/echidna.yaml`: `testLimit` 60000, `seqLen` 320). Each job has a 180-minute cap and Echidna `--timeout` 9000s so setup plus fuzzing fit under the GitHub Actions limit and a timeout still uploads artifacts. On failure the workflow uploads `echidna/logs/`, corpus reproducers under `echidna/corpus/by-contract/`, and `crytic-export/` as artifacts.
+
+CI does not pin `ECHIDNA_SEED` (a new seed each run). To replay a CI counterexample, copy `Seed: N` from the uploaded log and pass it locally:
+
+```bash
+ECHIDNA_CONTRACT=EchidnaStakeRegistryHarness \
+ECHIDNA_SEED=N \
+yarn echidna
+```
 
 ## Extend
 
diff --git a/scripts/echidna.sh b/scripts/echidna.sh
index 50d454b4..aad8e8db 100755
--- a/scripts/echidna.sh
+++ b/scripts/echidna.sh
@@ -13,6 +13,7 @@ cd "$ROOT_DIR"
 IMAGE="${ECHIDNA_IMAGE:-ghcr.io/crytic/echidna/echidna:latest}"
 CONTRACT="${ECHIDNA_CONTRACT:-}"
 CONFIG="${ECHIDNA_CONFIG:-echidna/echidna.yaml}"
+LOG_DIR="${ECHIDNA_LOG_DIR:-echidna/logs}"
 
 # Crytic-compile reads artifacts/build-info when using --hardhat-ignore-compile inside Docker (no Node/npx).
 # Stale build-info from deleted Solidity sources causes "Unknown file" failures.
@@ -40,6 +41,7 @@ fi
 # echidna/echidna.yaml: testLimit 60000, seqLen 320). Examples:
 #   ECHIDNA_TEST_LIMIT=20000 ECHIDNA_SEQ_LEN=200 yarn echidna   # faster smoke
 #   ECHIDNA_WORKERS=8 ECHIDNA_CONTRACT=EchidnaSystemHarness yarn echidna
+#   ECHIDNA_SEED=1 ECHIDNA_TIMEOUT=600 yarn echidna            # reproducible / time-boxed CI run
 # Use a string (not an array) so `set -u` never trips on empty `${arr[*]}` on older Bash.
 ECHIDNA_EXTRA_CLI=""
 if [[ -n "${ECHIDNA_TEST_LIMIT:-}" ]]; then
@@ -51,6 +53,17 @@ fi
 if [[ -n "${ECHIDNA_WORKERS:-}" ]]; then
   ECHIDNA_EXTRA_CLI+=" --workers ${ECHIDNA_WORKERS}"
 fi
+if [[ -n "${ECHIDNA_SEED:-}" ]]; then
+  ECHIDNA_EXTRA_CLI+=" --seed ${ECHIDNA_SEED}"
+fi
+if [[ -n "${ECHIDNA_TIMEOUT:-}" ]]; then
+  ECHIDNA_EXTRA_CLI+=" --timeout ${ECHIDNA_TIMEOUT}"
+fi
+if [[ -n "${ECHIDNA_ARGS:-}" ]]; then
+  ECHIDNA_EXTRA_CLI+=" ${ECHIDNA_ARGS}"
+fi
+
+mkdir -p "${ROOT_DIR}/${LOG_DIR}"
 
 for c in "${CONTRACTS_TO_RUN[@]}"; do
   echo "==> echidna: running contract $c" >&2
@@ -58,10 +71,17 @@ for c in "${CONTRACTS_TO_RUN[@]}"; do
   # One corpus + coverage tree per harness so saved sequences stay relevant to
   # that contract (shared corpus mixed unrelated call shapes and diluted learning).
   CORPUS_DIR="echidna/corpus/by-contract/${c}"
+  if [[ -n "${ECHIDNA_SEED:-}" ]]; then
+    CORPUS_DIR="${CORPUS_DIR}/seed-${ECHIDNA_SEED}"
+  fi
   mkdir -p "${ROOT_DIR}/${CORPUS_DIR}"
 
+  LOG_FILE="${ROOT_DIR}/${LOG_DIR}/${c}.log"
+
   # Drop stale Crytic output inside Docker (same uid as container root). A host
   # `rm -rf crytic-export` often fails after Docker created the dir as root.
+  # Capture the fuzzer exit code while still teeing logs for CI artifacts.
+  set +e
   docker run --rm \
     --entrypoint sh \
     -v "$ROOT_DIR":/src \
@@ -69,8 +89,16 @@ for c in "${CONTRACTS_TO_RUN[@]}"; do
     "$IMAGE" \
     -c "rm -rf crytic-export && echidna-test . --contract ${c} --config ${CONFIG} \
       --corpus-dir ${CORPUS_DIR} --coverage-dir ${CORPUS_DIR}/coverage${ECHIDNA_EXTRA_CLI} \
-      --crytic-args '--hardhat-ignore-compile'"
+      --crytic-args '--hardhat-ignore-compile'" \
+    2>&1 | tee "${LOG_FILE}"
+  ec=${PIPESTATUS[0]}
+  set -e
 
   yarn -s ts-node "${ROOT_DIR}/scripts/echidna-coverage-summary.ts" "${c}" \
     --coverage-dir "${ROOT_DIR}/${CORPUS_DIR}/coverage" || true
+
+  if [[ "${ec}" -ne 0 ]]; then
+    echo "==> echidna: ${c} failed (exit ${ec}); log: ${LOG_FILE}" >&2
+    exit "${ec}"
+  fi
 done