diff --git a/.woodpecker/ci.yml b/.woodpecker/ci.yml
index 57c69b6..7f14b68 100644
--- a/.woodpecker/ci.yml
+++ b/.woodpecker/ci.yml
@@ -57,6 +57,19 @@ steps:
   # NOTE: contracts-base-sepolia step removed — requires base_sepolia_rpc secret
   # which is not configured. Re-add when RPC secret is provisioned.
 
+  - name: transpiler-tests
+    image: registry.niovi.voyage/harb/node-ci:latest
+    commands:
+      - |
+        bash -c '
+          set -euo pipefail
+          export PATH=/root/.foundry/bin:$PATH
+          cd tools/push3-transpiler
+          npm install --silent
+          bash test_inject_extraction.sh
+          bash test_transpiler_clamping.sh
+        '
+
   - name: single-package-manager
     image: registry.niovi.voyage/harb/node-ci:latest
     commands:
diff --git a/tools/push3-transpiler/test_inject_extraction.sh b/tools/push3-transpiler/test_inject_extraction.sh
index fb826b9..4ddad5d 100755
--- a/tools/push3-transpiler/test_inject_extraction.sh
+++ b/tools/push3-transpiler/test_inject_extraction.sh
@@ -5,6 +5,8 @@
 # Exit: 0 if all tests pass, 1 if any fail.
 set -euo pipefail
 
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+
 PASS=0
 FAIL=0
 
@@ -155,6 +157,56 @@ else
   PASS=$((PASS + 1))
 fi
 
+# ── Test 5: forge build on transpiled optimizer_seed.push3 ───────────────────
+echo "Test 5: forge build on transpiled optimizer_seed.push3 (compile regression guard)"
+
+REPO_ROOT="$(cd "$SCRIPT_DIR/../.." && pwd)"
+TMPDIR_I5=$(mktemp -d)
+trap 'rm -rf "$TMPDIR_I5"' EXIT
+
+if [ ! -d "$SCRIPT_DIR/node_modules" ]; then
+  (cd "$SCRIPT_DIR" && npm install --silent)
+fi
+
+SOL_OUT="$TMPDIR_I5/OptimizerV3Push3.sol"
+TRANSPILE_RC=0
+(cd "$SCRIPT_DIR" && node --loader ts-node/esm src/index.ts \
+  "$REPO_ROOT/tools/push3-transpiler/optimizer_seed.push3" "$SOL_OUT") \
+  >/dev/null 2>&1 || TRANSPILE_RC=$?
+
+if [ "$TRANSPILE_RC" -ne 0 ]; then
+  echo "  FAIL: transpiler failed on optimizer_seed.push3"
+  FAIL=$((FAIL + 1))
+else
+  FORGE_BIN="$(command -v forge 2>/dev/null || true)"
+  if [ -z "$FORGE_BIN" ] && [ -x /root/.foundry/bin/forge ]; then
+    FORGE_BIN=/root/.foundry/bin/forge
+  fi
+
+  if [ -z "$FORGE_BIN" ]; then
+    echo "  SKIP: forge not found — add foundry bin to PATH to enable compile verification"
+  else
+    FORGE_DIR="$TMPDIR_I5/forge_verify"
+    mkdir -p "$FORGE_DIR/src"
+    printf '[profile.default]\nsrc = "src"\nout = "out"\nlibs = []\nvia_ir = true\n' > "$FORGE_DIR/foundry.toml"
+    cp "$REPO_ROOT/onchain/src/IOptimizer.sol" "$FORGE_DIR/src/"
+    cp "$SOL_OUT" "$FORGE_DIR/src/OptimizerV3Push3.sol"
+
+    FORGE_OUT=""
+    FORGE_RC=0
+    FORGE_OUT=$(cd "$FORGE_DIR" && "$FORGE_BIN" build 2>&1) || FORGE_RC=$?
+
+    if [ "$FORGE_RC" -eq 0 ]; then
+      echo "  PASS: forge build succeeded on transpiled optimizer_seed.push3"
+      PASS=$((PASS + 1))
+    else
+      echo "  FAIL: forge build failed on transpiled optimizer_seed.push3"
+      echo "$FORGE_OUT" | sed 's/^/      /'
+      FAIL=$((FAIL + 1))
+    fi
+  fi
+fi
+
 # ── Summary ──────────────────────────────────────────────────────────────────
 echo ""
 echo "Results: $PASS passed, $FAIL failed"
diff --git a/tools/push3-transpiler/test_transpiler_clamping.sh b/tools/push3-transpiler/test_transpiler_clamping.sh
index 93da1b7..48155c2 100755
--- a/tools/push3-transpiler/test_transpiler_clamping.sh
+++ b/tools/push3-transpiler/test_transpiler_clamping.sh
@@ -185,6 +185,38 @@ assert_contains \
   "$STDERR" \
   "anchorWidth literal (-1) is outside uint24 range [0, 16777215]"
 
+# ── Test 11: forge build — transpiler output compiles (regression for #900) ──
+echo "Test 11: forge build on valid transpiler output (regression for #900)"
+
+REPO_ROOT="$(cd "$SCRIPT_DIR/../.." && pwd)"
+FORGE_BIN="$(command -v forge 2>/dev/null || true)"
+if [ -z "$FORGE_BIN" ] && [ -x /root/.foundry/bin/forge ]; then
+  FORGE_BIN=/root/.foundry/bin/forge
+fi
+
+if [ -z "$FORGE_BIN" ]; then
+  echo "  SKIP: forge not found — add foundry bin to PATH to enable compile verification"
+else
+  FORGE_DIR="$TMPDIR_T/forge_verify"
+  mkdir -p "$FORGE_DIR/src"
+  printf '[profile.default]\nsrc = "src"\nout = "out"\nlibs = []\nvia_ir = true\n' > "$FORGE_DIR/foundry.toml"
+  cp "$REPO_ROOT/onchain/src/IOptimizer.sol" "$FORGE_DIR/src/"
+  cp "$OUTPUT_6" "$FORGE_DIR/src/OptimizerV3Push3.sol"
+
+  FORGE_OUT=""
+  FORGE_RC=0
+  FORGE_OUT=$(cd "$FORGE_DIR" && "$FORGE_BIN" build 2>&1) || FORGE_RC=$?
+
+  if [ "$FORGE_RC" -eq 0 ]; then
+    echo "  PASS: forge build succeeded on transpiled contract"
+    PASS=$((PASS + 1))
+  else
+    echo "  FAIL: forge build failed — transpiled contract does not compile"
+    echo "$FORGE_OUT" | sed 's/^/      /'
+    FAIL=$((FAIL + 1))
+  fi
+fi
+
 # ── Summary ──────────────────────────────────────────────────────────────────
 echo ""
 echo "Results: $PASS passed, $FAIL failed"