diff --git a/neko/index.js b/neko/index.js
index 77894208..54ceecb3 100644
--- a/neko/index.js
+++ b/neko/index.js
@@ -274,6 +274,7 @@ const {
 	extractHost,
 	toPuny,
 	toPunyOptional,
+	convertToHiddenPost,
 	sqlLikeEscape,
 	safeForSql,
 	formatMilliseconds,
@@ -293,6 +294,7 @@ module.exports.isSelfHost = isSelfHost;
 module.exports.extractHost = extractHost;
 module.exports.toPuny = toPuny;
 module.exports.toPunyOptional = toPunyOptional;
+module.exports.convertToHiddenPost = convertToHiddenPost;
 module.exports.sqlLikeEscape = sqlLikeEscape;
 module.exports.safeForSql = safeForSql;
 module.exports.formatMilliseconds = formatMilliseconds;
diff --git a/packages/backend/native-utils/Cargo.toml b/packages/backend/native-utils/Cargo.toml
index fa51f43e..01e6f064 100644
--- a/packages/backend/native-utils/Cargo.toml
+++ b/packages/backend/native-utils/Cargo.toml
@@ -8,7 +8,7 @@ members = ["migration"]
 
 [features]
 default = []
-napi = ["dep:napi", "dep:napi-derive"]
+napi = ["dep:napi-derive"]
 
 [lib]
 crate-type = ["cdylib", "lib"]
@@ -35,7 +35,7 @@ url = "2.5.0"
 utoipa = "4.1.0"
 
 # Default enable napi4 feature, see https://nodejs.org/api/n-api.html#node-api-version-matrix
-napi = { version = "2.14.1", default-features = false, features = ["napi9", "tokio_rt"], optional = true }
+napi = { version = "2.14.1", default-features = false, features = ["napi9", "tokio_rt"] }
 napi-derive = { version = "2.14.5", optional = true }
 basen = "0.1.0"
 
diff --git a/packages/backend/native-utils/src/util/convert_to_hidden_post.rs b/packages/backend/native-utils/src/util/convert_to_hidden_post.rs
new file mode 100644
index 00000000..3a713f68
--- /dev/null
+++ b/packages/backend/native-utils/src/util/convert_to_hidden_post.rs
@@ -0,0 +1,25 @@
+use napi;
+
+#[cfg_attr(feature = "napi", napi_derive::napi(object))]
+pub struct Post {
+    pub text: Option<String>,
+    pub cw: Option<String>,
+    pub local_only: bool,
+    pub created_at: napi::JsDate,
+    /// FIXME: introduce enum type (and remove "hiddensomething" visibility if possible)
+    pub visibility: String,
+}
+
+#[cfg_attr(feature = "napi", napi_derive::napi)]
+pub fn convert_to_hidden_post(original_post: Post) -> Post {
+    Post {
+        text: match original_post.text {
+            Some(s) if !s.is_empty() => Some(s),
+            _ => None,
+        },
+        cw: original_post.cw,
+        local_only: original_post.local_only,
+        created_at: original_post.created_at,
+        visibility: format!("hidden{}", original_post.visibility),
+    }
+}
diff --git a/packages/backend/native-utils/src/util/mod.rs b/packages/backend/native-utils/src/util/mod.rs
index 4c20f677..441b0325 100644
--- a/packages/backend/native-utils/src/util/mod.rs
+++ b/packages/backend/native-utils/src/util/mod.rs
@@ -1,6 +1,7 @@
 pub mod acct;
 pub mod config;
 pub mod convert_host;
+pub mod convert_to_hidden_post;
 pub mod escape_sql;
 pub mod format_milliseconds;
 pub mod id;
diff --git a/packages/backend/src/misc/post.ts b/packages/backend/src/misc/post.ts
deleted file mode 100644
index 0b107ed0..00000000
--- a/packages/backend/src/misc/post.ts
+++ /dev/null
@@ -1,21 +0,0 @@
-export type Post = {
-	text: string | undefined;
-	cw: string | null;
-	localOnly: boolean;
-	createdAt: Date;
-	visibility: string;
-};
-
-export function parse(acct: any): Post {
-	return {
-		text: acct.text || undefined,
-		cw: acct.cw,
-		localOnly: acct.localOnly,
-		createdAt: new Date(acct.createdAt),
-		visibility: `hidden${acct.visibility || ""}`,
-	};
-}
-
-export function toJson(acct: Post): string {
-	return { text: acct.text, cw: acct.cw, localOnly: acct.localOnly }.toString();
-}
diff --git a/packages/backend/src/queue/processors/db/import-firefish-post.ts b/packages/backend/src/queue/processors/db/import-firefish-post.ts
index 65879601..5d33488d 100644
--- a/packages/backend/src/queue/processors/db/import-firefish-post.ts
+++ b/packages/backend/src/queue/processors/db/import-firefish-post.ts
@@ -1,4 +1,4 @@
-import * as Post from "@/misc/post.js";
+import { convertToHiddenPost } from "native-utils/built/index.js";
 import create from "@/services/note/create.js";
 import { Users } from "@/models/index.js";
 import type { DbUserImportMastoPostJobData } from "@/queue/types.js";
@@ -52,7 +52,8 @@ export async function importCkPost(
 			logger.error(`Skipped adding file to drive: ${url}`);
 		}
 	}
-	const { text, cw, localOnly, createdAt, visibility } = Post.parse(post);
+	const { text, cw, localOnly, createdAt, visibility } =
+		convertToHiddenPost(post);
 	let note = await Notes.findOneBy({
 		createdAt: createdAt,
 		text: text,