diff --git a/tests/api-exercise-test.sh b/tests/api-exercise-test.sh
index 3a778a2f3..bccf1c24a 100755
--- a/tests/api-exercise-test.sh
+++ b/tests/api-exercise-test.sh
@@ -115,6 +115,74 @@ check() {
   return 0
 }
 
+# Make an API request returning both status and body (separated by newline)
+api_full() {
+  local method="$1"
+  local path="$2"
+  local body="${3:-}"
+  local url="${BASE_URL}${path}"
+
+  local curl_args=(-s -w "\n%{http_code}" -b "$COOKIE_FILE" -c "$COOKIE_FILE")
+  curl_args+=(-X "$method")
+
+  if [ -n "$CSRF_TOKEN" ]; then
+    curl_args+=(-H "X-CSRF-Token: $CSRF_TOKEN")
+  fi
+
+  if [ -n "$body" ]; then
+    curl_args+=(-H "Content-Type: application/json")
+    curl_args+=(-d "$body")
+  fi
+
+  curl "${curl_args[@]}" "$url" 2>/dev/null || echo -e "\n000"
+}
+
+# Check response status AND validate JSON body structure using Python
+# Usage: check_json "description" "METHOD" "/path" "python_validation_expr"
+# The python expression receives the parsed JSON as 'data' and should return True/False
+# Example: check_json "GET /api/nodes" "GET" "/api/nodes" "isinstance(data, list) and len(data) >= 0"
+check_json() {
+  local desc="$1"
+  local method="$2"
+  local path="$3"
+  local validation="$4"
+  local expected_status="${5:-200}"
+
+  local response
+  response=$(api_full "$method" "$path")
+  local status
+  status=$(echo "$response" | tail -1)
+  local body
+  body=$(echo "$response" | sed '$d')
+
+  if [ "$status" != "$expected_status" ]; then
+    log_fail "$desc" "HTTP ${status} (expected ${expected_status})"
+    return 0
+  fi
+
+  # Validate JSON structure
+  local valid
+  valid=$(echo "$body" | python3 -c "
+import sys, json
+try:
+    data = json.load(sys.stdin)
+    result = bool(${validation})
+    print('OK' if result else 'FAIL')
+except Exception as e:
+    print(f'ERR:{e}')
+" 2>/dev/null || echo "ERR:python failed")
+
+  if [ "$valid" = "OK" ]; then
+    log_pass "$desc (${status}, body validated)"
+  elif [[ "$valid" == ERR:* ]]; then
+    log_fail "$desc" "JSON parse error: ${valid#ERR:}"
+  else
+    log_fail "$desc" "body validation failed (HTTP ${status})"
+  fi
+
+  return 0
+}
+
 # ─── Setup ─────────────────────────────────────────────────
 
 echo "=========================================="
@@ -193,18 +261,18 @@ check "GET /api/auth/status (authenticated)" "$(api GET /api/auth/status)" 200
 echo ""
 echo -e "${BLUE}=== Nodes ===${NC}"
 
-check "GET /api/status" "$(api GET /api/status)" 200
-check "GET /api/stats" "$(api GET /api/stats)" 200
-check "GET /api/config" "$(api GET /api/config)" 200
-check "GET /api/config/current" "$(api GET /api/config/current)" 200
-check "GET /api/connection" "$(api GET /api/connection)" 200
-check "GET /api/connection/info" "$(api GET /api/connection/info)" 200
+check_json "GET /api/status" "GET" "/api/status" "'status' in data"
+check_json "GET /api/stats" "GET" "/api/stats" "'messageCount' in data and 'nodeCount' in data and 'channelCount' in data"
+check_json "GET /api/config" "GET" "/api/config" "isinstance(data, dict)"
+check_json "GET /api/config/current" "GET" "/api/config/current" "isinstance(data, dict)"
+check_json "GET /api/connection" "GET" "/api/connection" "'connected' in data"
+check_json "GET /api/connection/info" "GET" "/api/connection/info" "isinstance(data, dict)"
 check "GET /api/version/check" "$(api GET /api/version/check)" 200
-check "GET /api/virtual-node/status" "$(api GET /api/virtual-node/status)" 200
-check "GET /api/nodes" "$(api GET /api/nodes)" 200
-check "GET /api/nodes/active" "$(api GET /api/nodes/active)" 200
-check "GET /api/nodes/security-issues" "$(api GET /api/nodes/security-issues)" 200
-check "GET /api/ignored-nodes" "$(api GET /api/ignored-nodes)" 200
+check_json "GET /api/virtual-node/status" "GET" "/api/virtual-node/status" "'enabled' in data"
+check_json "GET /api/nodes" "GET" "/api/nodes" "isinstance(data, list)"
+check_json "GET /api/nodes/active" "GET" "/api/nodes/active" "isinstance(data, list)"
+check_json "GET /api/nodes/security-issues" "GET" "/api/nodes/security-issues" "isinstance(data, list)"
+check_json "GET /api/ignored-nodes" "GET" "/api/ignored-nodes" "isinstance(data, list)"
 check "GET /api/auto-favorite/status" "$(api GET /api/auto-favorite/status)" 200
 check "GET /api/device/tx-status" "$(api GET /api/device/tx-status)" 200
 check "GET /api/device/security-keys" "$(api GET /api/device/security-keys)" 200
@@ -237,7 +305,7 @@ fi
 echo ""
 echo -e "${BLUE}=== Telemetry ===${NC}"
 
-check "GET /api/telemetry/available/nodes" "$(api GET /api/telemetry/available/nodes)" 200
+check_json "GET /api/telemetry/available/nodes" "GET" "/api/telemetry/available/nodes" "isinstance(data, (list, dict))"
 
 if [ -n "$FIRST_NODE_ID" ]; then
   check "GET /api/telemetry/:nodeId" "$(api GET /api/telemetry/$FIRST_NODE_ID)" 200
@@ -253,17 +321,17 @@ fi
 echo ""
 echo -e "${BLUE}=== Messages ===${NC}"
 
-check "GET /api/messages" "$(api GET /api/messages)" 200
-check "GET /api/messages/channel/0" "$(api GET /api/messages/channel/0)" 200
-check "GET /api/messages/search?q=test" "$(api GET '/api/messages/search?q=test')" 200
-check "GET /api/messages/unread-counts" "$(api GET /api/messages/unread-counts)" 200
+check_json "GET /api/messages" "GET" "/api/messages" "isinstance(data, list)"
+check_json "GET /api/messages/channel/0" "GET" "/api/messages/channel/0" "'messages' in data"
+check_json "GET /api/messages/search?q=test" "GET" "/api/messages/search?q=test" "'success' in data and 'data' in data"
+check_json "GET /api/messages/unread-counts" "GET" "/api/messages/unread-counts" "'channels' in data"
 
 # ─── Traceroutes ───────────────────────────────────────────
 
 echo ""
 echo -e "${BLUE}=== Traceroutes ===${NC}"
 
-check "GET /api/traceroutes/recent" "$(api GET /api/traceroutes/recent)" 200
+check_json "GET /api/traceroutes/recent" "GET" "/api/traceroutes/recent" "isinstance(data, list)"
 check "GET /api/route-segments/record-holder" "$(api GET /api/route-segments/record-holder)" 200
 check "GET /api/route-segments/longest-active" "$(api GET /api/route-segments/longest-active)" 200
 
@@ -284,8 +352,8 @@ fi
 echo ""
 echo -e "${BLUE}=== Channels ===${NC}"
 
-check "GET /api/channels" "$(api GET /api/channels)" 200
-check "GET /api/channels/all" "$(api GET /api/channels/all)" 200
+check_json "GET /api/channels" "GET" "/api/channels" "isinstance(data, list)"
+check_json "GET /api/channels/all" "GET" "/api/channels/all" "isinstance(data, list)"
 check "GET /api/channels/debug" "$(api GET /api/channels/debug)" 200
 
 # ─── Packets ──────────────────────────────────────────────
@@ -293,10 +361,10 @@ check "GET /api/channels/debug" "$(api GET /api/channels/debug)" 200
 echo ""
 echo -e "${BLUE}=== Packets ===${NC}"
 
-check "GET /api/packets" "$(api GET /api/packets)" 200
-check "GET /api/packets?limit=10" "$(api GET '/api/packets?limit=10')" 200
-check "GET /api/packets/stats" "$(api GET /api/packets/stats)" 200
-check "GET /api/packets/stats/distribution" "$(api GET /api/packets/stats/distribution)" 200
+check_json "GET /api/packets" "GET" "/api/packets" "'packets' in data and 'total' in data"
+check_json "GET /api/packets?limit=10" "GET" "/api/packets?limit=10" "'packets' in data and isinstance(data['packets'], list)"
+check_json "GET /api/packets/stats" "GET" "/api/packets/stats" "'total' in data"
+check_json "GET /api/packets/stats/distribution" "GET" "/api/packets/stats/distribution" "'byDevice' in data and 'byType' in data"
 check "GET /api/packets/relay-nodes" "$(api GET /api/packets/relay-nodes)" 200
 check "GET /api/packets/export?limit=10" "$(api GET '/api/packets/export?limit=10')" 200
 
@@ -305,18 +373,19 @@ check "GET /api/packets/export?limit=10" "$(api GET '/api/packets/export?limit=1
 echo ""
 echo -e "${BLUE}=== Audit Logs ===${NC}"
 
-check "GET /api/audit" "$(api GET /api/audit)" 200
-check "GET /api/audit?limit=10" "$(api GET '/api/audit?limit=10')" 200
-check "GET /api/audit/stats/summary" "$(api GET /api/audit/stats/summary)" 200
+check_json "GET /api/audit" "GET" "/api/audit" "'logs' in data and 'total' in data"
+check_json "GET /api/audit?limit=10" "GET" "/api/audit?limit=10" "'logs' in data and 'total' in data"
+check_json "GET /api/audit/stats/summary" "GET" "/api/audit/stats/summary" "isinstance(data, dict)"
 
 # ─── Security ─────────────────────────────────────────────
 
 echo ""
 echo -e "${BLUE}=== Security ===${NC}"
 
-check "GET /api/security/issues" "$(api GET /api/security/issues)" 200
-check "GET /api/security/scanner/status" "$(api GET /api/security/scanner/status)" 200
-check "GET /api/security/key-mismatches" "$(api GET /api/security/key-mismatches)" 200
+check_json "GET /api/security/issues" "GET" "/api/security/issues" "'total' in data and 'nodes' in data"
+check_json "GET /api/security/scanner/status" "GET" "/api/security/scanner/status" "'running' in data"
+check_json "GET /api/security/key-mismatches" "GET" "/api/security/key-mismatches" "'events' in data"
+check_json "GET /api/security/dead-nodes" "GET" "/api/security/dead-nodes" "'nodes' in data and 'count' in data"
 check "GET /api/security/export" "$(api GET /api/security/export)" 200
 
 # ─── User Management ──────────────────────────────────────
@@ -324,7 +393,7 @@ check "GET /api/security/export" "$(api GET /api/security/export)" 200
 echo ""
 echo -e "${BLUE}=== User Management ===${NC}"
 
-check "GET /api/users" "$(api GET /api/users)" 200
+check_json "GET /api/users" "GET" "/api/users" "isinstance(data, (list, dict)) and (isinstance(data, list) or 'users' in data)"
 
 ADMIN_ID=$(api_body GET /api/users | python3 -c "
 import sys,json
@@ -379,10 +448,10 @@ check "GET /api/token" "$(api GET /api/token)" 200
 echo ""
 echo -e "${BLUE}=== Settings ===${NC}"
 
-check "GET /api/settings" "$(api GET /api/settings)" 200
+check_json "GET /api/settings" "GET" "/api/settings" "isinstance(data, dict)"
 check "POST /api/settings (no-op)" "$(api POST /api/settings '{}')" 200
-check "GET /api/settings/traceroute-nodes" "$(api GET /api/settings/traceroute-nodes)" 200
-check "GET /api/settings/traceroute-log" "$(api GET /api/settings/traceroute-log)" 200
+check_json "GET /api/settings/traceroute-nodes" "GET" "/api/settings/traceroute-nodes" "isinstance(data, (list, dict))"
+check_json "GET /api/settings/traceroute-log" "GET" "/api/settings/traceroute-log" "'success' in data and 'log' in data"
 check "GET /api/settings/time-sync-nodes" "$(api GET /api/settings/time-sync-nodes)" 200
 check "GET /api/settings/auto-ping" "$(api GET /api/settings/auto-ping)" 200
 check "GET /api/settings/key-repair-log" "$(api GET /api/settings/key-repair-log)" 200
@@ -455,19 +524,19 @@ check "GET /api/embed-profiles" "$(api GET /api/embed-profiles)" 200
 echo ""
 echo -e "${BLUE}=== Maintenance ===${NC}"
 
-check "GET /api/maintenance/status" "$(api GET /api/maintenance/status)" 200
-check "GET /api/maintenance/size" "$(api GET /api/maintenance/size)" 200
+check_json "GET /api/maintenance/status" "GET" "/api/maintenance/status" "isinstance(data, dict)"
+check_json "GET /api/maintenance/size" "GET" "/api/maintenance/size" "isinstance(data, dict)"
 
 # ─── Backups ──────────────────────────────────────────────
 
 echo ""
 echo -e "${BLUE}=== Backups ===${NC}"
 
-check "GET /api/backup/list" "$(api GET /api/backup/list)" 200
-check "GET /api/backup/settings" "$(api GET /api/backup/settings)" 200
-check "GET /api/system/backup/list" "$(api GET /api/system/backup/list)" 200
-check "GET /api/system/backup/settings" "$(api GET /api/system/backup/settings)" 200
-check "GET /api/system/status" "$(api GET /api/system/status)" 200
+check_json "GET /api/backup/list" "GET" "/api/backup/list" "isinstance(data, list)"
+check_json "GET /api/backup/settings" "GET" "/api/backup/settings" "isinstance(data, dict)"
+check_json "GET /api/system/backup/list" "GET" "/api/system/backup/list" "isinstance(data, list)"
+check_json "GET /api/system/backup/settings" "GET" "/api/system/backup/settings" "isinstance(data, dict)"
+check_json "GET /api/system/status" "GET" "/api/system/status" "isinstance(data, dict)"
 
 # ─── Ghost Nodes ──────────────────────────────────────────
 
@@ -535,17 +604,63 @@ if [ -n "$API_TOKEN" ]; then
       "$url" 2>/dev/null || echo "000"
   }
 
-  check "GET /api/v1" "$(v1 GET /api/v1)" 200
-  check "GET /api/v1/nodes" "$(v1 GET /api/v1/nodes)" 200
-  check "GET /api/v1/channels" "$(v1 GET /api/v1/channels)" 200
-  check "GET /api/v1/messages" "$(v1 GET /api/v1/messages)" 200
-  check "GET /api/v1/telemetry" "$(v1 GET /api/v1/telemetry)" 200
-  check "GET /api/v1/traceroutes" "$(v1 GET /api/v1/traceroutes)" 200
-  check "GET /api/v1/network" "$(v1 GET /api/v1/network)" 200
-  check "GET /api/v1/network/topology" "$(v1 GET /api/v1/network/topology)" 200
-  check "GET /api/v1/network/direct-neighbors" "$(v1 GET /api/v1/network/direct-neighbors)" 200
-  check "GET /api/v1/packets" "$(v1 GET /api/v1/packets)" 200
-  check "GET /api/v1/channel-database" "$(v1 GET /api/v1/channel-database)" 200
+  # V1 API needs its own check_json since it uses Bearer token auth
+  v1_body() {
+    local method="$1"
+    local path="$2"
+    local url="${BASE_URL}${path}"
+    curl -s -w "\n%{http_code}" -X "$method" \
+      -H "Authorization: Bearer $API_TOKEN" \
+      "$url" 2>/dev/null || echo -e "\n000"
+  }
+
+  check_v1() {
+    local desc="$1"
+    local path="$2"
+    local validation="$3"
+    local response
+    response=$(v1_body GET "$path")
+    local status
+    status=$(echo "$response" | tail -1)
+    local body
+    body=$(echo "$response" | sed '$d')
+
+    if [ "$status" != "200" ]; then
+      log_fail "$desc" "HTTP ${status} (expected 200)"
+      return 0
+    fi
+
+    local valid
+    valid=$(echo "$body" | python3 -c "
+import sys, json
+try:
+    data = json.load(sys.stdin)
+    result = bool(${validation})
+    print('OK' if result else 'FAIL')
+except Exception as e:
+    print(f'ERR:{e}')
+" 2>/dev/null || echo "ERR:python failed")
+
+    if [ "$valid" = "OK" ]; then
+      log_pass "$desc (200, body validated)"
+    elif [[ "$valid" == ERR:* ]]; then
+      log_fail "$desc" "JSON parse error: ${valid#ERR:}"
+    else
+      log_fail "$desc" "body validation failed"
+    fi
+  }
+
+  check_v1 "GET /api/v1" "/api/v1" "'version' in data or 'success' in data"
+  check_v1 "GET /api/v1/nodes" "/api/v1/nodes" "'success' in data and 'data' in data"
+  check_v1 "GET /api/v1/channels" "/api/v1/channels" "'success' in data and 'data' in data"
+  check_v1 "GET /api/v1/messages" "/api/v1/messages" "'success' in data and 'data' in data"
+  check_v1 "GET /api/v1/telemetry" "/api/v1/telemetry" "'success' in data or isinstance(data, dict)"
+  check_v1 "GET /api/v1/traceroutes" "/api/v1/traceroutes" "'success' in data and 'data' in data"
+  check_v1 "GET /api/v1/network" "/api/v1/network" "'success' in data and 'data' in data"
+  check_v1 "GET /api/v1/network/topology" "/api/v1/network/topology" "'success' in data and 'data' in data"
+  check_v1 "GET /api/v1/network/direct-neighbors" "/api/v1/network/direct-neighbors" "'success' in data or isinstance(data, dict)"
+  check_v1 "GET /api/v1/packets" "/api/v1/packets" "'success' in data and 'data' in data"
+  check_v1 "GET /api/v1/channel-database" "/api/v1/channel-database" "'success' in data and 'data' in data"
   check "GET /api/v1/solar" "$(v1 GET /api/v1/solar)" 200
   check "GET /api/v1/solar/range" "$(v1 GET '/api/v1/solar/range?start=0&end=9999999999999')" 200
   check "GET /api/v1/messages/search?q=test" "$(v1 GET '/api/v1/messages/search?q=test')" 200
diff --git a/tests/system-tests.sh b/tests/system-tests.sh
index c93101078..741864ba4 100755
--- a/tests/system-tests.sh
+++ b/tests/system-tests.sh
@@ -172,6 +172,7 @@ else
     BACKUP_RESTORE_RESULT="SKIPPED"
     DB_MIGRATION_RESULT="SKIPPED"
     DB_BACKING_RESULT="SKIPPED"
+    API_EXERCISE_RESULT="SKIPPED"
     # Skip to results
     echo ""
     echo "=========================================="
@@ -188,6 +189,7 @@ else
     echo -e "Backup & Restore Test:    ${YELLOW}⊘ SKIPPED${NC}"
     echo -e "Database Migration Test:  ${YELLOW}⊘ SKIPPED${NC}"
     echo -e "DB Backing Consistency:  ${YELLOW}⊘ SKIPPED${NC}"
+    echo -e "API Exercise (3 DBs):    ${YELLOW}⊘ SKIPPED${NC}"
     echo ""
     echo -e "${RED}===========================================${NC}"
     echo -e "${RED}✗ SYSTEM TESTS FAILED${NC}"
@@ -342,6 +344,23 @@ else
 fi
 echo ""
 
+echo "=========================================="
+echo -e "${BLUE}Running API Exercise Test (All Backends)${NC}"
+echo "=========================================="
+echo ""
+
+# Run API Exercise test on all 3 database backends
+if bash "$SCRIPT_DIR/test-api-exercise-all-backends.sh"; then
+    API_EXERCISE_RESULT="PASSED"
+    echo ""
+    echo -e "${GREEN}✓ API Exercise test PASSED (all backends)${NC}"
+else
+    API_EXERCISE_RESULT="FAILED"
+    echo ""
+    echo -e "${RED}✗ API Exercise test FAILED${NC}"
+fi
+echo ""
+
 # Summary
 echo "=========================================="
 echo "System Test Results"
@@ -412,6 +431,14 @@ else
     echo -e "DB Backing Consistency:  ${RED}✗ FAILED${NC}"
 fi
 
+if [ "$API_EXERCISE_RESULT" = "PASSED" ]; then
+    echo -e "API Exercise (3 DBs):    ${GREEN}✓ PASSED${NC}"
+elif [ "$API_EXERCISE_RESULT" = "SKIPPED" ]; then
+    echo -e "API Exercise (3 DBs):    ${YELLOW}⊘ SKIPPED${NC}"
+else
+    echo -e "API Exercise (3 DBs):    ${RED}✗ FAILED${NC}"
+fi
+
 echo ""
 
 # Generate markdown report
@@ -489,11 +516,19 @@ else
     echo "| DB Backing Consistency | ❌ FAILED |" >> "$REPORT_FILE"
 fi
 
+if [ "$API_EXERCISE_RESULT" = "PASSED" ]; then
+    echo "| API Exercise (3 DBs) | ✅ PASSED |" >> "$REPORT_FILE"
+elif [ "$API_EXERCISE_RESULT" = "SKIPPED" ]; then
+    echo "| API Exercise (3 DBs) | ⊘ SKIPPED |" >> "$REPORT_FILE"
+else
+    echo "| API Exercise (3 DBs) | ❌ FAILED |" >> "$REPORT_FILE"
+fi
+
 echo "" >> "$REPORT_FILE"
 
 # Overall result (config import is optional, so only fail if it actually failed, not if skipped)
 REQUIRED_TESTS_PASSED=true
-if [ "$QUICKSTART_RESULT" != "PASSED" ] || [ "$SECURITY_RESULT" != "PASSED" ] || [ "$V1_API_RESULT" != "PASSED" ] || [ "$REVERSE_PROXY_RESULT" != "PASSED" ] || [ "$OIDC_RESULT" != "PASSED" ] || [ "$VIRTUAL_NODE_CLI_RESULT" != "PASSED" ] || [ "$BACKUP_RESTORE_RESULT" != "PASSED" ] || [ "$DB_MIGRATION_RESULT" != "PASSED" ] || [ "$DB_BACKING_RESULT" != "PASSED" ]; then
+if [ "$QUICKSTART_RESULT" != "PASSED" ] || [ "$SECURITY_RESULT" != "PASSED" ] || [ "$V1_API_RESULT" != "PASSED" ] || [ "$REVERSE_PROXY_RESULT" != "PASSED" ] || [ "$OIDC_RESULT" != "PASSED" ] || [ "$VIRTUAL_NODE_CLI_RESULT" != "PASSED" ] || [ "$BACKUP_RESTORE_RESULT" != "PASSED" ] || [ "$DB_MIGRATION_RESULT" != "PASSED" ] || [ "$DB_BACKING_RESULT" != "PASSED" ] || [ "$API_EXERCISE_RESULT" != "PASSED" ]; then
     REQUIRED_TESTS_PASSED=false
 fi
 
diff --git a/tests/test-api-exercise-all-backends.sh b/tests/test-api-exercise-all-backends.sh
new file mode 100755
index 000000000..bb9c9551f
--- /dev/null
+++ b/tests/test-api-exercise-all-backends.sh
@@ -0,0 +1,156 @@
+#!/bin/bash
+# API Exercise Test — All Database Backends
+#
+# Runs the API exercise test against SQLite, PostgreSQL, and MySQL backends
+# to verify response structure consistency across all databases.
+#
+# Usage: tests/test-api-exercise-all-backends.sh
+
+set -e
+
+echo "=========================================="
+echo "API Exercise Test — All Backends"
+echo "=========================================="
+echo ""
+
+# Colors
+GREEN='\033[0;32m'
+RED='\033[0;31m'
+YELLOW='\033[1;33m'
+BLUE='\033[0;34m'
+NC='\033[0m'
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
+COMPOSE_FILE="docker-compose.dev.yml"
+
+cd "$PROJECT_ROOT"
+
+# Backend definitions: profile -> compose service name
+declare -A BACKENDS
+BACKENDS[sqlite]="meshmonitor-sqlite"
+BACKENDS[postgres]="meshmonitor"
+BACKENDS[mysql]="meshmonitor-mysql"
+
+# Port for dev containers
+DEV_PORT=8081
+BASE_URL="http://localhost:${DEV_PORT}/meshmonitor"
+
+# Track results
+TOTAL_PASS=0
+TOTAL_FAIL=0
+RESULTS=()
+
+cleanup() {
+    echo -e "${BLUE}Cleaning up all backends...${NC}"
+    for profile in sqlite postgres mysql; do
+        COMPOSE_PROFILES="$profile" docker compose -f "$COMPOSE_FILE" down -v 2>/dev/null || true
+    done
+}
+
+trap cleanup EXIT
+
+# Pre-flight: stop any running dev containers and clean up volumes
+echo -e "${BLUE}Stopping any running dev containers...${NC}"
+for profile in sqlite postgres mysql; do
+    COMPOSE_PROFILES="$profile" docker compose -f "$COMPOSE_FILE" down -v --remove-orphans 2>/dev/null || true
+done
+# Extra cleanup: kill any leftover containers on port 8081
+docker ps --filter "publish=8081" -q 2>/dev/null | xargs -r docker stop 2>/dev/null || true
+sleep 2
+
+for profile in sqlite postgres mysql; do
+    CONTAINER="${BACKENDS[$profile]}"
+
+    echo ""
+    echo "=========================================="
+    echo -e "${BLUE}Testing $profile backend${NC}"
+    echo "=========================================="
+
+    # Start backend
+    echo -e "${BLUE}Starting $profile...${NC}"
+    COMPOSE_PROFILES="$profile" docker compose -f "$COMPOSE_FILE" up -d 2>/dev/null
+
+    # MySQL needs extra time for database initialization
+    if [ "$profile" = "mysql" ]; then
+        echo -e "${BLUE}Waiting for MySQL database to be healthy...${NC}"
+        for i in $(seq 1 60); do
+            if COMPOSE_PROFILES="$profile" docker compose -f "$COMPOSE_FILE" ps 2>/dev/null | grep -q "healthy"; then
+                echo -e "${GREEN}✓ MySQL database healthy${NC}"
+                break
+            fi
+            sleep 3
+        done
+    fi
+
+    # Wait for container to be healthy (up to 3 minutes)
+    echo -e "${BLUE}Waiting for $CONTAINER to be ready...${NC}"
+    READY=false
+    for i in $(seq 1 90); do
+        if COMPOSE_PROFILES="$profile" docker compose -f "$COMPOSE_FILE" ps "$CONTAINER" 2>/dev/null | grep -q "Up"; then
+            # Check if API responds
+            HTTP_STATUS=$(curl -s -o /dev/null -w "%{http_code}" "${BASE_URL}/api/health" 2>/dev/null || echo "000")
+            if [ "$HTTP_STATUS" = "200" ] || [ "$HTTP_STATUS" = "404" ]; then
+                # Also check auth endpoint (more reliable)
+                HTTP_STATUS=$(curl -s -o /dev/null -w "%{http_code}" "${BASE_URL}/api/csrf-token" 2>/dev/null || echo "000")
+                if [ "$HTTP_STATUS" = "200" ]; then
+                    READY=true
+                    break
+                fi
+            fi
+        fi
+        sleep 2
+    done
+
+    if [ "$READY" = false ]; then
+        echo -e "${RED}✗ $profile backend failed to start${NC}"
+        RESULTS+=("$profile: FAILED (startup)")
+        TOTAL_FAIL=$((TOTAL_FAIL + 1))
+        COMPOSE_PROFILES="$profile" docker compose -f "$COMPOSE_FILE" down -v 2>/dev/null || true
+        continue
+    fi
+
+    echo -e "${GREEN}✓ $profile backend ready${NC}"
+
+    # Run the API exercise test
+    if bash "$SCRIPT_DIR/api-exercise-test.sh" "$BASE_URL"; then
+        echo -e "${GREEN}✓ $profile: API exercise test PASSED${NC}"
+        RESULTS+=("$profile: PASSED")
+        TOTAL_PASS=$((TOTAL_PASS + 1))
+    else
+        echo -e "${RED}✗ $profile: API exercise test FAILED${NC}"
+        RESULTS+=("$profile: FAILED")
+        TOTAL_FAIL=$((TOTAL_FAIL + 1))
+    fi
+
+    # Stop backend and clean volumes
+    echo -e "${BLUE}Stopping $profile...${NC}"
+    COMPOSE_PROFILES="$profile" docker compose -f "$COMPOSE_FILE" down -v --remove-orphans 2>/dev/null || true
+    sleep 3
+done
+
+# Summary
+echo ""
+echo "=========================================="
+echo "API Exercise Test — All Backends Results"
+echo "=========================================="
+
+for result in "${RESULTS[@]}"; do
+    profile="${result%%:*}"
+    status="${result#*: }"
+    if [ "$status" = "PASSED" ]; then
+        echo -e "  ${GREEN}✓${NC} $profile: PASS"
+    else
+        echo -e "  ${RED}✗${NC} $profile: FAIL"
+    fi
+done
+
+echo ""
+
+if [ $TOTAL_FAIL -gt 0 ]; then
+    echo -e "${RED}✗ API EXERCISE TEST FAILED ($TOTAL_FAIL backend(s) failed)${NC}"
+    exit 1
+else
+    echo -e "${GREEN}✓ ALL BACKENDS PASSED${NC}"
+    exit 0
+fi