diff --git a/xtraplatform-cache/src/main/java/de/ii/xtraplatform/cache/app/CacheDriverFs.java b/xtraplatform-cache/src/main/java/de/ii/xtraplatform/cache/app/CacheDriverFs.java
index 4d3d787b..361e8a1c 100644
--- a/xtraplatform-cache/src/main/java/de/ii/xtraplatform/cache/app/CacheDriverFs.java
+++ b/xtraplatform-cache/src/main/java/de/ii/xtraplatform/cache/app/CacheDriverFs.java
@@ -32,6 +32,7 @@
 
 @Singleton
 @AutoBind
+@SuppressWarnings("PMD.TooManyMethods")
 public class CacheDriverFs implements CacheDriver {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(CacheDriverFs.class);
@@ -137,18 +138,20 @@ private <T> T read(String key, String validator, Class<T> clazz) {
     }
   }
 
-  private synchronized void write(String key, String validator, Object value, int ttl) {
+  private void write(String key, String validator, Object value, int ttl) {
     Path entry = keyPath(key);
     try {
       byte[] serialized = serialize(value);
 
-      Files.createDirectories(entry);
-      Files.write(entry.resolve(validator), serialized);
-      if (ttl > 0) {
-        long expires = Instant.now().toEpochMilli() + (ttl * 1000L);
-        Files.writeString(entry.resolve(TTL), Long.toString(expires));
-      } else {
-        Files.deleteIfExists(entry.resolve(TTL));
+      synchronized (this) {
+        Files.createDirectories(entry);
+        Files.write(entry.resolve(validator), serialized);
+        if (ttl > 0) {
+          long expires = Instant.now().toEpochMilli() + (ttl * 1000L);
+          Files.writeString(entry.resolve(TTL), Long.toString(expires));
+        } else {
+          Files.deleteIfExists(entry.resolve(TTL));
+        }
       }
     } catch (IOException e) {
       // ignore
@@ -175,11 +178,13 @@ private <T> T deserialize(byte[] value, Class<T> clazz) throws IOException {
     return valueEncoding.getMapper(FORMAT.SMILE).readValue(value, clazz);
   }
 
-  private synchronized void delete(String key) {
-    try (Stream<Path> entries = Files.walk(keyPath(key))) {
-      entries.sorted(Comparator.reverseOrder()).map(Path::toFile).forEach(File::delete);
-    } catch (IOException e) {
-      // ignore
+  private void delete(String key) {
+    synchronized (this) {
+      try (Stream<Path> entries = Files.walk(keyPath(key))) {
+        entries.sorted(Comparator.reverseOrder()).map(Path::toFile).forEach(File::delete);
+      } catch (IOException e) {
+        // ignore
+      }
     }
   }
 
diff --git a/xtraplatform-cache/src/main/java/de/ii/xtraplatform/cache/app/CacheDriverMem.java b/xtraplatform-cache/src/main/java/de/ii/xtraplatform/cache/app/CacheDriverMem.java
index c8b604dc..dcf1934f 100644
--- a/xtraplatform-cache/src/main/java/de/ii/xtraplatform/cache/app/CacheDriverMem.java
+++ b/xtraplatform-cache/src/main/java/de/ii/xtraplatform/cache/app/CacheDriverMem.java
@@ -22,6 +22,7 @@
 
 @Singleton
 @AutoBind
+@SuppressWarnings("PMD.TooManyMethods")
 public class CacheDriverMem implements CacheDriver {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(CacheDriverMem.class);
@@ -101,12 +102,16 @@ public void del(String key) {
     delete(key);
   }
 
-  private synchronized void set(String key, Map<String, Object> entry) {
-    cache.put(key, entry);
+  private void set(String key, Map<String, Object> entry) {
+    synchronized (cache) {
+      cache.put(key, entry);
+    }
   }
 
-  private synchronized void delete(String key) {
-    cache.remove(key);
+  private void delete(String key) {
+    synchronized (cache) {
+      cache.remove(key);
+    }
   }
 
   private void checkExpired(String key) {
diff --git a/xtraplatform-cache/src/main/java/de/ii/xtraplatform/cache/app/CacheImpl.java b/xtraplatform-cache/src/main/java/de/ii/xtraplatform/cache/app/CacheImpl.java
index 9e9b649c..5ae1fa43 100644
--- a/xtraplatform-cache/src/main/java/de/ii/xtraplatform/cache/app/CacheImpl.java
+++ b/xtraplatform-cache/src/main/java/de/ii/xtraplatform/cache/app/CacheImpl.java
@@ -9,7 +9,6 @@
 
 import com.github.azahnen.dagger.annotations.AutoBind;
 import dagger.Lazy;
-import de.ii.xtraplatform.base.domain.AppContext;
 import de.ii.xtraplatform.base.domain.AppLifeCycle;
 import de.ii.xtraplatform.cache.domain.Cache;
 import de.ii.xtraplatform.cache.domain.CacheDriver;
@@ -33,8 +32,7 @@ public class CacheImpl implements Cache, AppLifeCycle {
   private CacheDriver driver;
 
   @Inject
-  public CacheImpl(AppContext appContext, Lazy<Set<CacheDriver>> drivers) {
-    // TODO appContext.getConfiguration().getCache();
+  public CacheImpl(Lazy<Set<CacheDriver>> drivers) {
     this.drivers = drivers;
   }