diff --git a/src/main/kotlin/dev/usbharu/hideout/repository/IPostRepository.kt b/src/main/kotlin/dev/usbharu/hideout/repository/IPostRepository.kt
index 3b77248e..7321fbf7 100644
--- a/src/main/kotlin/dev/usbharu/hideout/repository/IPostRepository.kt
+++ b/src/main/kotlin/dev/usbharu/hideout/repository/IPostRepository.kt
@@ -1,11 +1,23 @@
 package dev.usbharu.hideout.repository
 
 import dev.usbharu.hideout.domain.model.hideout.entity.Post
+import java.time.Instant
 
 interface IPostRepository {
     suspend fun generateId(): Long
     suspend fun save(post: Post): Post
-    suspend fun findOneById(id: Long): Post?
+    suspend fun findOneById(id: Long, userId: Long? = null): Post?
     suspend fun findByUrl(url: String): Post?
     suspend fun delete(id: Long)
+    suspend fun findAll(since: Instant?, until: Instant?, minId: Long?, maxId: Long?, limit: Int?, userId: Long?): List<Post>
+    suspend fun findByUserNameAndDomain(username: String,
+                                        s: String,
+                                        since: Instant?,
+                                        until: Instant?,
+                                        minId: Long?,
+                                        maxId: Long?,
+                                        limit: Int?,
+                                        userId: Long?): List<Post>
+
+    suspend fun findByUserId(idOrNull: Long, since: Instant?, until: Instant?, minId: Long?, maxId: Long?, limit: Int?, userId: Long?): List<Post>
 }
diff --git a/src/main/kotlin/dev/usbharu/hideout/routing/api/internal/v1/Posts.kt b/src/main/kotlin/dev/usbharu/hideout/routing/api/internal/v1/Posts.kt
index ee533159..2312d575 100644
--- a/src/main/kotlin/dev/usbharu/hideout/routing/api/internal/v1/Posts.kt
+++ b/src/main/kotlin/dev/usbharu/hideout/routing/api/internal/v1/Posts.kt
@@ -1,9 +1,7 @@
 package dev.usbharu.hideout.routing.api.internal.v1
 
-import dev.usbharu.hideout.domain.model.hideout.dto.PostCreateDto
 import dev.usbharu.hideout.domain.model.hideout.form.Post
 import dev.usbharu.hideout.exception.ParameterNotExistException
-import dev.usbharu.hideout.exception.PostNotFoundException
 import dev.usbharu.hideout.plugins.TOKEN_AUTH
 import dev.usbharu.hideout.service.api.IPostApiService
 import dev.usbharu.hideout.util.InstantParseUtil
@@ -24,15 +22,7 @@ fun Route.posts(postApiService: IPostApiService) {
                 val userId = principal.payload.getClaim("uid").asLong()
 
                 val receive = call.receive<Post>()
-                val postCreateDto = PostCreateDto(
-                        text = receive.text,
-                        overview = receive.overview,
-                        visibility = receive.visibility,
-                        repostId = receive.repostId,
-                        repolyId = receive.replyId,
-                        userId = userId
-                )
-                val create = postApiService.createPost(postCreateDto)
+                val create = postApiService.createPost(receive, userId)
                 call.response.header("Location", create.url)
                 call.respond(HttpStatusCode.OK)
             }
diff --git a/src/main/kotlin/dev/usbharu/hideout/service/api/IPostApiService.kt b/src/main/kotlin/dev/usbharu/hideout/service/api/IPostApiService.kt
index d54d48cb..00b6ff03 100644
--- a/src/main/kotlin/dev/usbharu/hideout/service/api/IPostApiService.kt
+++ b/src/main/kotlin/dev/usbharu/hideout/service/api/IPostApiService.kt
@@ -1,11 +1,10 @@
 package dev.usbharu.hideout.service.api
 
-import dev.usbharu.hideout.domain.model.hideout.dto.PostCreateDto
 import dev.usbharu.hideout.domain.model.hideout.entity.Post
 import java.time.Instant
 
 interface IPostApiService {
-    suspend fun createPost(postCreateDto: PostCreateDto): Post
+    suspend fun createPost(postForm: dev.usbharu.hideout.domain.model.hideout.form.Post, userId: Long): Post
     suspend fun getById(id: Long, userId: Long?): Post
     suspend fun getAll(since: Instant? = null,
                        until: Instant? = null,
diff --git a/src/main/kotlin/dev/usbharu/hideout/service/api/PostApiServiceImpl.kt b/src/main/kotlin/dev/usbharu/hideout/service/api/PostApiServiceImpl.kt
new file mode 100644
index 00000000..9061224e
--- /dev/null
+++ b/src/main/kotlin/dev/usbharu/hideout/service/api/PostApiServiceImpl.kt
@@ -0,0 +1,45 @@
+package dev.usbharu.hideout.service.api
+
+import dev.usbharu.hideout.config.Config
+import dev.usbharu.hideout.domain.model.hideout.dto.PostCreateDto
+import dev.usbharu.hideout.domain.model.hideout.entity.Post
+import dev.usbharu.hideout.exception.PostNotFoundException
+import dev.usbharu.hideout.repository.IPostRepository
+import dev.usbharu.hideout.service.post.IPostService
+import dev.usbharu.hideout.util.AcctUtil
+import org.koin.core.annotation.Single
+import java.time.Instant
+
+@Single
+class PostApiServiceImpl(private val postService: IPostService, private val postRepository: IPostRepository) : IPostApiService {
+    override suspend fun createPost(postForm: dev.usbharu.hideout.domain.model.hideout.form.Post, userId: Long): Post {
+        return postService.createLocal(PostCreateDto(
+                text = postForm.text,
+                overview = postForm.overview,
+                visibility = postForm.visibility,
+                repostId = postForm.repostId,
+                repolyId = postForm.replyId,
+                userId = userId
+        ))
+    }
+
+    override suspend fun getById(id: Long, userId: Long?): Post {
+        return postRepository.findOneById(id, userId)
+                ?: throw PostNotFoundException("$id was not found or is not authorized.")
+    }
+
+    override suspend fun getAll(since: Instant?, until: Instant?, minId: Long?, maxId: Long?, limit: Int?, userId: Long?): List<Post> {
+        return postRepository.findAll(since, until, minId, maxId, limit, userId)
+    }
+
+    override suspend fun getByUser(nameOrId: String, since: Instant?, until: Instant?, minId: Long?, maxId: Long?, limit: Int?, userId: Long?): List<Post> {
+        val idOrNull = nameOrId.toLongOrNull()
+        return if (idOrNull == null) {
+            val acct = AcctUtil.parse(nameOrId)
+            postRepository.findByUserNameAndDomain(acct.username, acct.domain
+                    ?: Config.configData.domain, since, until, minId, maxId, limit, userId)
+        } else {
+            postRepository.findByUserId(idOrNull, since, until, minId, maxId, limit, userId)
+        }
+    }
+}
diff --git a/src/main/kotlin/dev/usbharu/hideout/service/post/IPostService.kt b/src/main/kotlin/dev/usbharu/hideout/service/post/IPostService.kt
index 970eaa26..298dae0a 100644
--- a/src/main/kotlin/dev/usbharu/hideout/service/post/IPostService.kt
+++ b/src/main/kotlin/dev/usbharu/hideout/service/post/IPostService.kt
@@ -1,9 +1,10 @@
 package dev.usbharu.hideout.service.post
 
 import dev.usbharu.hideout.domain.model.ap.Note
+import dev.usbharu.hideout.domain.model.hideout.dto.PostCreateDto
 import dev.usbharu.hideout.domain.model.hideout.entity.Post
 
 interface IPostService {
-    suspend fun createLocal(post: Post): Post
+    suspend fun createLocal(post: PostCreateDto): Post
     suspend fun createRemote(note: Note): Post
 }