diff --git a/.github/workflows/deno.yml b/.github/workflows/deno.yml
new file mode 100644
index 0000000..607d4f0
--- /dev/null
+++ b/.github/workflows/deno.yml
@@ -0,0 +1,62 @@
+name: Deno
+
+on:
+  push:
+    branches: ["main"]
+    tags: 
+      - '*'
+  pull_request:
+    branches: ["main"]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Setup repo
+        uses: actions/checkout@v3
+
+      - name: Setup Deno
+        # uses: denoland/setup-deno@v1
+        uses: denoland/setup-deno@61fe2df320078202e33d7d5ad347e7dcfa0e8f31  # v1.1.2
+        with:
+          deno-version: v1.x
+          
+      - name: Verify formatting
+        run: deno fmt --check
+
+      - name: Run linter
+        run: deno lint
+
+      - name: Run tests
+        run: deno test -A
+
+  npm_publish:
+    name: Publish to npm
+    needs: test
+    if: startsWith(github.ref, 'refs/tags/')
+    runs-on: ubuntu-latest
+    steps:
+      - name: Get tag version
+        id: get_tag_version
+        run: echo TAG_VERSION=${GITHUB_REF/refs\/tags\//} >> $GITHUB_OUTPUT
+
+      - name: Setup Deno
+        # uses: denoland/setup-deno@v1
+        uses: denoland/setup-deno@61fe2df320078202e33d7d5ad347e7dcfa0e8f31  # v1.1.2
+        with:
+          deno-version: v1.x
+        
+      - name: Setup Node
+        uses: actions/setup-node@v3
+        with:
+          node-version: '18.x'
+          registry-url: 'https://registry.npmjs.org'
+          
+      - name: npm build
+        run: deno task build ${{steps.get_tag_version.outputs.TAG_VERSION}}
+        
+      - name: npm publish
+        env:
+          NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
+        run: cd npm && npm publish
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..50d08d0
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+npm
\ No newline at end of file
diff --git a/.vscode/settings.json b/.vscode/settings.json
new file mode 100644
index 0000000..fdbe9bd
--- /dev/null
+++ b/.vscode/settings.json
@@ -0,0 +1,4 @@
+{
+  "deno.enable": true,
+  "editor.defaultFormatter": "denoland.vscode-deno"
+}
diff --git a/README.md b/README.md
index a8d2ddd..564f727 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,43 @@
-# file-reader-promise
\ No newline at end of file
+# file-reader-promise
+
+Promise-based [`FileReader`](https://developer.mozilla.org/docs/Web/API/FileReader) implementation.
+
+## Installation
+
+node
+
+```sh
+npm install @myrear/file-reader-promise
+```
+
+deno
+
+```ts
+import {
+  FileReader,
+  readAs,
+} from 'https://deno.land/x/file-reader-promise/mod.ts'
+```
+
+## Usage
+
+This library provides 2 modules:
+
+- [`readAs`](#readas)
+- [`FileReader`](#filereader) 
+  
+  Thin wrapper class for the web standard [`FileReader`](https://developer.mozilla.org/docs/Web/API/FileReader) class
+
+### `readAs`
+
+```ts
+const result: string = await readAs(reader, file, 'DataURL')
+const result: ArrayBuffer = await readAs(reader, file, 'ArrayBuffer')
+```
+
+### `FileReader`
+
+```ts
+const result: string = await new FileReader().readAsDataURL(file)
+const result: ArrayBuffer = await new FileReader().readAsArrayBuffer(file)
+```
diff --git a/__tests__/FileReader.test.ts b/__tests__/FileReader.test.ts
new file mode 100644
index 0000000..4e1d358
--- /dev/null
+++ b/__tests__/FileReader.test.ts
@@ -0,0 +1,40 @@
+import './setup.ts'
+import { FileReader } from '../src/FileReader.ts'
+import { assertEquals } from 'std/assert/assert_equals.ts'
+import { assertInstanceOf } from 'std/assert/assert_instance_of.ts'
+
+Deno.test('read blob', async (t) => {
+  const blob = new Blob(['foo'], { type: 'text/plain' })
+
+  await t.step('as `ArrayBuffer`', async () => {
+    const reader = new FileReader()
+    const result = await reader.readAsArrayBuffer(blob)
+
+    assertEquals(result, reader.result)
+    assertInstanceOf(result, ArrayBuffer)
+  })
+
+  await t.step('as `BinaryString`', async () => {
+    const reader = new FileReader()
+    const result = await reader.readAsBinaryString(blob)
+
+    assertEquals(result, reader.result)
+    assertEquals(result, 'foo')
+  })
+
+  await t.step('as `DataURL`', async () => {
+    const reader = new FileReader()
+    const result = await reader.readAsDataURL(blob)
+
+    assertEquals(result, reader.result)
+    assertEquals(result, 'data:text/plain;base64,Zm9v')
+  })
+
+  await t.step('as `Text` with encoding utf-8', async () => {
+    const reader = new FileReader()
+    const result = await reader.readAsText(blob, 'utf-8')
+
+    assertEquals(result, reader.result)
+    assertEquals(result, 'foo')
+  })
+})
diff --git a/__tests__/readAs.test.ts b/__tests__/readAs.test.ts
new file mode 100644
index 0000000..0b69447
--- /dev/null
+++ b/__tests__/readAs.test.ts
@@ -0,0 +1,60 @@
+import './setup.ts'
+import { assertEquals, assertInstanceOf } from 'std/assert/mod.ts'
+import { assertSpyCall, spy } from 'std/testing/mock.ts'
+import { readAs } from '../src/readAs.ts'
+
+Deno.test('read blob', async (t) => {
+  const blob = new Blob(['foo'], { type: 'text/plain' })
+
+  await t.step('as `ArrayBuffer`', async () => {
+    const reader = new FileReader()
+    const readAsArrayBufferSpy = spy(reader, 'readAsArrayBuffer')
+    const result = await readAs(reader, blob, 'ArrayBuffer')
+
+    assertEquals(result, reader.result)
+    assertInstanceOf(result, ArrayBuffer)
+    assertSpyCall(readAsArrayBufferSpy, 0, {
+      self: reader,
+      args: [blob, undefined],
+    })
+  })
+
+  await t.step('as `BinaryString`', async () => {
+    const reader = new FileReader()
+    const readAsBinaryStringSpy = spy(reader, 'readAsBinaryString')
+    const result = await readAs(reader, blob, 'BinaryString')
+
+    assertEquals(result, reader.result)
+    assertEquals(result, 'foo')
+    assertSpyCall(readAsBinaryStringSpy, 0, {
+      self: reader,
+      args: [blob, undefined],
+    })
+  })
+
+  await t.step('as `DataURL`', async () => {
+    const reader = new FileReader()
+    const readAsDataURLSpy = spy(reader, 'readAsDataURL')
+    const result = await readAs(reader, blob, 'DataURL')
+
+    assertEquals(result, reader.result)
+    assertEquals(result, 'data:text/plain;base64,Zm9v')
+    assertSpyCall(readAsDataURLSpy, 0, {
+      self: reader,
+      args: [blob, undefined],
+    })
+  })
+
+  await t.step('as `Text` with encoding utf-8', async () => {
+    const reader = new FileReader()
+    const readAsTextSpy = spy(reader, 'readAsText')
+    const result = await readAs(reader, blob, 'Text', 'utf-8')
+
+    assertEquals(result, reader.result)
+    assertEquals(typeof result, 'string')
+    assertSpyCall(readAsTextSpy, 0, {
+      self: reader,
+      args: [blob, 'utf-8'],
+    })
+  })
+})
diff --git a/__tests__/setup.ts b/__tests__/setup.ts
new file mode 100644
index 0000000..e582d82
--- /dev/null
+++ b/__tests__/setup.ts
@@ -0,0 +1,8 @@
+import { JSDOM } from 'jsdom'
+import { isNode } from 'which_runtime/mod.ts'
+
+if (isNode) {
+  const { window: { Blob, FileReader } } = new JSDOM()
+  globalThis.Blob = Blob
+  globalThis.FileReader = FileReader
+}
diff --git a/deno.jsonc b/deno.jsonc
new file mode 100644
index 0000000..ae359d4
--- /dev/null
+++ b/deno.jsonc
@@ -0,0 +1,17 @@
+{
+  "tasks": {
+    "build": "deno run -A npm_build.ts"
+  },
+  "fmt": {
+    "semiColons": false,
+    "singleQuote": true,
+    "exclude": ["*.md"]
+  },
+  "exclude": ["npm/**/*"],
+  "imports": {
+    "dnt/": "https://deno.land/x/dnt@0.38.1/",
+    "std/": "https://deno.land/std@0.199.0/",
+    "jsdom": "https://esm.sh/jsdom@22.1.0",
+    "which_runtime/": "https://deno.land/x/which_runtime@0.2.0/"
+  }
+}
diff --git a/deno.lock b/deno.lock
new file mode 100644
index 0000000..d2e6c69
--- /dev/null
+++ b/deno.lock
@@ -0,0 +1,181 @@
+{
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+  },
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+    "specifiers": {
+      "@types/node": "@types/node@18.16.19"
+    },
+    "packages": {
+      "@types/node@18.16.19": {
+        "integrity": "sha512-IXl7o+R9iti9eBW4Wg2hx1xQDig183jj7YLn8F7udNceyfkbn1ZxmzZXuak20gR40D7pIkIY1kYGx5VIGbaHKA==",
+        "dependencies": {}
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+  }
+}
diff --git a/npm_build.ts b/npm_build.ts
new file mode 100644
index 0000000..dbc67b8
--- /dev/null
+++ b/npm_build.ts
@@ -0,0 +1,37 @@
+import { build, emptyDir } from 'dnt/mod.ts'
+
+await emptyDir('./npm')
+
+await build({
+  entryPoints: ['./src/mod.ts'],
+  outDir: './npm',
+  shims: {
+    deno: { test: 'dev' },
+  },
+  compilerOptions: {
+    lib: ['ESNext', 'DOM'],
+  },
+  typeCheck: 'both',
+  importMap: 'deno.jsonc',
+  package: {
+    name: '@myrear/file-reader-promise',
+    description: 'Promise-based FileReader implementation.',
+    author: 'myrear',
+    license: 'MIT',
+    version: Deno.args[0],
+    repository: {
+      type: 'git',
+      url: 'https://github.com/myrear/file-reader-promise.git',
+    },
+    bugs: {
+      url: 'https://github.com/myrear/file-reader-promise/issues',
+    },
+    devDependencies: {
+      '@types/jsdom': '^21.1.1',
+    },
+  },
+  postBuild() {
+    Deno.copyFileSync('LICENSE', 'npm/LICENSE')
+    Deno.copyFileSync('README.md', 'npm/README.md')
+  },
+})
diff --git a/src/FileReader.ts b/src/FileReader.ts
new file mode 100644
index 0000000..697236c
--- /dev/null
+++ b/src/FileReader.ts
@@ -0,0 +1,27 @@
+import { promisifyReader } from './promisifyReader.ts'
+
+export class FileReader extends globalThis.FileReader {
+  readAsArrayBuffer(blob: Blob): Promise<ArrayBuffer>
+  readAsArrayBuffer(blob: Blob) {
+    super.readAsArrayBuffer(blob)
+    return promisifyReader(this)
+  }
+
+  readAsBinaryString(blob: Blob): Promise<string>
+  readAsBinaryString(blob: Blob) {
+    super.readAsBinaryString(blob)
+    return promisifyReader(this)
+  }
+
+  readAsDataURL(blob: Blob): Promise<string>
+  readAsDataURL(blob: Blob) {
+    super.readAsDataURL(blob)
+    return promisifyReader(this)
+  }
+
+  readAsText(blob: Blob, encoding?: string): Promise<string>
+  readAsText(blob: Blob, encoding?: string) {
+    super.readAsText(blob, encoding)
+    return promisifyReader(this)
+  }
+}
diff --git a/src/mod.ts b/src/mod.ts
new file mode 100644
index 0000000..2a79fe5
--- /dev/null
+++ b/src/mod.ts
@@ -0,0 +1,2 @@
+export * from './readAs.ts'
+export * from './FileReader.ts'
diff --git a/src/promisifyReader.ts b/src/promisifyReader.ts
new file mode 100644
index 0000000..4b146bc
--- /dev/null
+++ b/src/promisifyReader.ts
@@ -0,0 +1,18 @@
+export const promisifyReader = (reader: FileReader) =>
+  new Promise<FileReader['result']>((resolve, reject) => {
+    reader.addEventListener('load', loadListener)
+    reader.addEventListener('error', reject)
+    reader.addEventListener('abort', reject)
+    reader.addEventListener('loadend', removeEventListener)
+
+    function removeEventListener() {
+      reader.removeEventListener('load', loadListener)
+      reader.removeEventListener('error', reject)
+      reader.removeEventListener('abort', reject)
+      reader.removeEventListener('loadend', removeEventListener)
+    }
+
+    function loadListener() {
+      resolve(reader.result)
+    }
+  })
diff --git a/src/readAs.ts b/src/readAs.ts
new file mode 100644
index 0000000..b043e07
--- /dev/null
+++ b/src/readAs.ts
@@ -0,0 +1,30 @@
+import { promisifyReader } from './promisifyReader.ts'
+
+export function readAs(
+  reader: FileReader,
+  blob: Blob,
+  as: 'ArrayBuffer',
+): Promise<ArrayBuffer>
+
+export function readAs(
+  reader: FileReader,
+  blob: Blob,
+  as: 'BinaryString' | 'DataURL',
+): Promise<string>
+
+export function readAs(
+  reader: FileReader,
+  blob: Blob,
+  as: 'Text',
+  encoding?: string,
+): Promise<string>
+
+export function readAs(
+  reader: FileReader,
+  blob: Blob,
+  as: 'ArrayBuffer' | 'DataURL' | 'Text' | 'BinaryString',
+  encoding?: string,
+) {
+  reader[`readAs${as}`](blob, encoding)
+  return promisifyReader(reader)
+}