diff --git a/packages/core/src/adapter/node.ts b/packages/core/src/adapter/node.ts
index c50a210..46dd0ec 100644
--- a/packages/core/src/adapter/node.ts
+++ b/packages/core/src/adapter/node.ts
@@ -3,6 +3,7 @@ import { basename } from 'node:path'
 import FileType from 'file-type'
 import { FileResponse } from '../index.js'
 import { readFile } from 'node:fs/promises'
+import { Binary } from 'cosmokit'
 
 export { lookup } from 'node:dns/promises'
 
@@ -10,9 +11,12 @@ export async function loadFile(url: string): Promise<FileResponse | undefined> {
   if (url.startsWith('file://')) {
     const data = await readFile(fileURLToPath(url))
     const result = await FileType.fromBuffer(data)
-    // https://stackoverflow.com/questions/8609289/convert-a-binary-nodejs-buffer-to-javascript-arraybuffer#answer-31394257
-    const buffer = data.buffer.slice(data.byteOffset, data.byteOffset + data.byteLength)
-    return { mime: result?.mime, filename: basename(url), data: buffer }
+    return {
+      type: result?.mime!,
+      mime: result?.mime,
+      filename: basename(url),
+      data: Binary.fromSource(data),
+    }
   }
 }
 
diff --git a/packages/core/src/index.ts b/packages/core/src/index.ts
index 91374f1..7af0a86 100644
--- a/packages/core/src/index.ts
+++ b/packages/core/src/index.ts
@@ -122,6 +122,8 @@ export interface FileConfig {
 }
 
 export interface FileResponse {
+  type: string
+  /** @deprecated use `type` instead */
   mime?: string
   filename: string
   data: ArrayBuffer
@@ -384,20 +386,20 @@ export class HTTP extends Service<HTTP.Config> {
     if (result) return result
     const capture = /^data:([\w/-]+);base64,(.*)$/.exec(url)
     if (capture) {
-      const [, mime, base64] = capture
+      const [, type, base64] = capture
       let name = 'file'
-      const ext = mime && mimedb[mime]?.extensions?.[0]
+      const ext = type && mimedb[type]?.extensions?.[0]
       if (ext) name += `.${ext}`
-      return { mime, data: Binary.fromBase64(base64), filename: name }
+      return { type, mime: type, data: Binary.fromBase64(base64), filename: name }
     }
     const { headers, data, url: responseUrl } = await this<ArrayBuffer>(url, {
       method: 'GET',
       responseType: 'arraybuffer',
       timeout: +options.timeout! || undefined,
     })
-    const mime = headers.get('content-type') ?? undefined
+    const type = headers.get('content-type')!
     const [, name] = responseUrl.match(/.+\/([^/?]*)(?=\?)?/)!
-    return { mime, filename: name, data }
+    return { type, mime: type, filename: name, data }
   }
 
   async isLocal(url: string) {