diff --git a/build.gradle.kts b/build.gradle.kts
index af9d60f7..a1912f3b 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -143,7 +143,6 @@ dependencies {
 
     implementation("org.drewcarlson:kjob-core:0.6.0")
     implementation("org.drewcarlson:kjob-mongo:0.6.0")
-    testImplementation("org.slf4j:slf4j-simple:2.0.7")
 
     detektPlugins("io.gitlab.arturbosch.detekt:detekt-formatting:1.23.1")
 }
diff --git a/src/main/kotlin/dev/usbharu/hideout/service/ap/resource/APResourceResolveServiceImpl.kt b/src/main/kotlin/dev/usbharu/hideout/service/ap/resource/APResourceResolveServiceImpl.kt
index 55d1faa2..3402aff4 100644
--- a/src/main/kotlin/dev/usbharu/hideout/service/ap/resource/APResourceResolveServiceImpl.kt
+++ b/src/main/kotlin/dev/usbharu/hideout/service/ap/resource/APResourceResolveServiceImpl.kt
@@ -8,17 +8,14 @@ import dev.usbharu.hideout.repository.UserRepository
 import io.ktor.client.*
 import io.ktor.client.request.*
 import io.ktor.client.statement.*
-import kotlinx.coroutines.delay
 import org.springframework.beans.factory.annotation.Qualifier
 import org.springframework.stereotype.Service
-import java.time.Instant
-import java.util.*
-import java.util.concurrent.ConcurrentHashMap
 
 @Service
 class APResourceResolveServiceImpl(
     private val httpClient: HttpClient,
     private val userRepository: UserRepository,
+    private val cacheManager: CacheManager,
     @Qualifier("activitypub") private val objectMapper: ObjectMapper
 ) :
     APResourceResolveService {
@@ -34,31 +31,19 @@ class APResourceResolveServiceImpl(
     private suspend fun internalResolve(url: String, singerId: Long?): Object {
 
         val key = genCacheKey(url, singerId)
-        val ifAbsent = cacheKey.putIfAbsent(key, Instant.now().toEpochMilli())
-        if (ifAbsent == null) {
-            val resolve = runResolve(url, singerId?.let { userRepository.findById(it) })
-            valueStore.putIfAbsent(key, resolve)
-            return resolve
+
+        cacheManager.putCache(key) {
+            runResolve(url, singerId?.let { userRepository.findById(it) })
         }
-        return wait(key)
+        return cacheManager.getOrWait(key)
     }
 
     private suspend fun internalResolve(url: String, singer: User?): Object {
         val key = genCacheKey(url, singer?.id)
-        val ifAbsent = cacheKey.putIfAbsent(key, Instant.now().toEpochMilli())
-        if (ifAbsent == null) {
-            val resolve = runResolve(url, singer)
-            valueStore.putIfAbsent(key, resolve)
-            return resolve
+        cacheManager.putCache(key) {
+            runResolve(url, singer)
         }
-        return wait(key)
-    }
-
-    private suspend fun wait(key: String): Object {
-        while (valueStore.containsKey(key).not()) {
-            delay(1)
-        }
-        return valueStore.getValue(key) as Object
+        return cacheManager.getOrWait(key)
     }
 
     private suspend fun runResolve(url: String, singer: User?): Object {
@@ -72,7 +57,4 @@ class APResourceResolveServiceImpl(
         }
         return url
     }
-
-    private val cacheKey = ConcurrentHashMap<String, Long>()
-    private val valueStore = Collections.synchronizedMap(mutableMapOf<String, Object>())
 }
diff --git a/src/main/kotlin/dev/usbharu/hideout/service/ap/resource/CacheManager.kt b/src/main/kotlin/dev/usbharu/hideout/service/ap/resource/CacheManager.kt
new file mode 100644
index 00000000..909e7c62
--- /dev/null
+++ b/src/main/kotlin/dev/usbharu/hideout/service/ap/resource/CacheManager.kt
@@ -0,0 +1,9 @@
+package dev.usbharu.hideout.service.ap.resource
+
+import dev.usbharu.hideout.domain.model.ap.Object
+
+interface CacheManager {
+
+    suspend fun putCache(key: String, block: suspend () -> Object)
+    suspend fun getOrWait(key: String): Object
+}
diff --git a/src/main/kotlin/dev/usbharu/hideout/service/ap/resource/InMemoryCacheManager.kt b/src/main/kotlin/dev/usbharu/hideout/service/ap/resource/InMemoryCacheManager.kt
new file mode 100644
index 00000000..be0abde5
--- /dev/null
+++ b/src/main/kotlin/dev/usbharu/hideout/service/ap/resource/InMemoryCacheManager.kt
@@ -0,0 +1,37 @@
+package dev.usbharu.hideout.service.ap.resource
+
+import dev.usbharu.hideout.domain.model.ap.Object
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+import org.springframework.stereotype.Service
+
+@Service
+class InMemoryCacheManager : CacheManager {
+    private val cacheKey = mutableSetOf<String>()
+    private val valueStore = mutableMapOf<String, Object>()
+    private val keyMutex = Mutex()
+
+    override suspend fun putCache(key: String, block: suspend () -> Object) {
+        val hasCache: Boolean
+        keyMutex.withLock {
+            hasCache = cacheKey.contains(key)
+            cacheKey.add(key)
+        }
+        if (hasCache.not()) {
+            val processed = block()
+
+            valueStore[key] = processed
+
+        }
+    }
+
+    override suspend fun getOrWait(key: String): Object {
+
+        while (valueStore.contains(key).not()) {
+            delay(1)
+        }
+        return valueStore.getValue(key)
+
+    }
+}
diff --git a/src/test/kotlin/dev/usbharu/hideout/service/ap/resource/APResourceResolveServiceImplTest.kt b/src/test/kotlin/dev/usbharu/hideout/service/ap/resource/APResourceResolveServiceImplTest.kt
index 226da282..16b171ff 100644
--- a/src/test/kotlin/dev/usbharu/hideout/service/ap/resource/APResourceResolveServiceImplTest.kt
+++ b/src/test/kotlin/dev/usbharu/hideout/service/ap/resource/APResourceResolveServiceImplTest.kt
@@ -49,7 +49,8 @@ class APResourceResolveServiceImplTest {
             )
         )
 
-        val apResourceResolveService = APResourceResolveServiceImpl(httpClient, userRepository, objectMapper)
+        val apResourceResolveService =
+            APResourceResolveServiceImpl(httpClient, userRepository, InMemoryCacheManager(), objectMapper)
 
         apResourceResolveService.resolve("https", 0)
 
@@ -83,7 +84,8 @@ class APResourceResolveServiceImplTest {
             )
         )
 
-        val apResourceResolveService = APResourceResolveServiceImpl(httpClient, userRepository, objectMapper)
+        val apResourceResolveService =
+            APResourceResolveServiceImpl(httpClient, userRepository, InMemoryCacheManager(), objectMapper)
 
         apResourceResolveService.resolve("https", 0)
         apResourceResolveService.resolve("https", 0)
@@ -120,7 +122,8 @@ class APResourceResolveServiceImplTest {
             )
         )
 
-        val apResourceResolveService = APResourceResolveServiceImpl(httpClient, userRepository, objectMapper)
+        val apResourceResolveService =
+            APResourceResolveServiceImpl(httpClient, userRepository, InMemoryCacheManager(), objectMapper)
 
         repeat(10) {
             awaitAll(
@@ -168,7 +171,8 @@ class APResourceResolveServiceImplTest {
             )
         )
 
-        val apResourceResolveService = APResourceResolveServiceImpl(httpClient, userRepository, objectMapper)
+        val apResourceResolveService =
+            APResourceResolveServiceImpl(httpClient, userRepository, InMemoryCacheManager(), objectMapper)
 
         apResourceResolveService.resolve("abcd", 0)
         apResourceResolveService.resolve("1234", 0)