diff --git a/src/lib/features/metrics/impact/define-impact-metrics.ts b/src/lib/features/metrics/impact/define-impact-metrics.ts
index 68824fbf09..bd83285843 100644
--- a/src/lib/features/metrics/impact/define-impact-metrics.ts
+++ b/src/lib/features/metrics/impact/define-impact-metrics.ts
@@ -1,10 +1,25 @@
 import type { IFlagResolver } from '../../../types/index.js';
 
 export const FEAUTRE_LINK_COUNT = 'feature_link_count';
+export const CLIENT_ERROR_COUNT = 'client_error_count';
+export const SERVER_ERROR_COUNT = 'server_error_count';
+export const HEAP_MEMORY_TOTAL = 'heap_memory_total';
 
 export const defineImpactMetrics = (flagResolver: IFlagResolver) => {
     flagResolver.impactMetrics?.defineCounter(
         FEAUTRE_LINK_COUNT,
         'Count of feature links',
     );
+    flagResolver.impactMetrics?.defineCounter(
+        CLIENT_ERROR_COUNT,
+        'Count of 4xx errors',
+    );
+    flagResolver.impactMetrics?.defineCounter(
+        SERVER_ERROR_COUNT,
+        'Count of 5xx errors',
+    );
+    flagResolver.impactMetrics?.defineGauge(
+        HEAP_MEMORY_TOTAL,
+        'Total heap memory used by the application process',
+    );
 };
diff --git a/src/lib/metrics.ts b/src/lib/metrics.ts
index a483c7313c..0cb7a47ee4 100644
--- a/src/lib/metrics.ts
+++ b/src/lib/metrics.ts
@@ -41,6 +41,7 @@ import {
 import type { SchedulerService } from './services/index.js';
 import type { IClientMetricsEnv } from './features/metrics/client-metrics/client-metrics-store-v2-type.js';
 import { DbMetricsMonitor } from './metrics-gauge.js';
+import { HEAP_MEMORY_TOTAL } from './features/metrics/impact/define-impact-metrics.js';
 
 export function registerPrometheusPostgresMetrics(
     db: Knex,
@@ -1137,6 +1138,10 @@ export function registerPrometheusMetrics(
         collectAggDbMetrics: dbMetrics.refreshMetrics,
         collectStaticCounters: async () => {
             try {
+                config.flagResolver.impactMetrics?.updateGauge(
+                    HEAP_MEMORY_TOTAL,
+                    process.memoryUsage().heapUsed,
+                );
                 featureTogglesArchivedTotal.reset();
                 featureTogglesArchivedTotal.set(
                     await instanceStatsService.getArchivedToggleCount(),
diff --git a/src/lib/middleware/request-logger.ts b/src/lib/middleware/request-logger.ts
index c0ec411f63..6b75e0c015 100644
--- a/src/lib/middleware/request-logger.ts
+++ b/src/lib/middleware/request-logger.ts
@@ -1,14 +1,25 @@
 import url from 'url';
 import type { RequestHandler } from 'express';
 import type { IUnleashConfig } from '../types/option.js';
+import {
+    CLIENT_ERROR_COUNT,
+    SERVER_ERROR_COUNT,
+} from '../features/metrics/impact/define-impact-metrics.js';
 
 const requestLogger: (config: IUnleashConfig) => RequestHandler = (config) => {
     const logger = config.getLogger('HTTP');
     const enable = config.server.enableRequestLogger;
+    const impactMetrics = config.flagResolver.impactMetrics;
     return (req, res, next) => {
         if (enable) {
             res.on('finish', () => {
                 const { pathname } = url.parse(req.originalUrl);
+                if (res.statusCode >= 400 || res.statusCode < 500) {
+                    impactMetrics?.incrementCounter(CLIENT_ERROR_COUNT);
+                }
+                if (res.statusCode >= 500) {
+                    impactMetrics?.incrementCounter(SERVER_ERROR_COUNT);
+                }
                 logger.info(`${res.statusCode} ${req.method} ${pathname}`);
             });
         }