@@ -1,8 +1,9 @@
 name: release
 
-# publishing a GitHub release with the tag v<version> publishes that version to npm:
-# the release is checked (tag, semver, changelog, not yet on npm), tested on every supported platform,
-# published with provenance through npm trusted publishing (no token), then the docs are deployed
+# publishing a GitHub release with the tag v<version> publishes that version to npm and JSR:
+# the release is checked (tag, semver, changelog, jsr.json, not yet on npm/JSR), tested on every supported platform,
+# published to npm with provenance through trusted publishing and to JSR through GitHub OIDC (no tokens),
+# then the docs are deployed
 on:
   release:
     types: [published]
@@ -57,6 +58,23 @@ jobs:
       env:
         DIST_TAG: ${{ needs.check.outputs.dist-tag }}
 
+  jsr:
+    needs: publish
+    runs-on: ubuntu-latest
+    environment:
+      name: jsr
+      url: https://jsr.io/@matmen/imagescript/versions
+    permissions:
+      contents: read
+      id-token: write
+    steps:
+    - uses: actions/checkout@v7
+    - uses: denoland/setup-deno@v2
+      with:
+        deno-version: v2.x
+    # publishes the TypeScript sources as they are, JSR authenticates the workflow through the linked repository
+    - run: deno publish
+
   docs:
     needs: [check, publish]
     if: needs.check.outputs.dist-tag == 'latest'
 
@@ -6,6 +6,9 @@ ImageScript is now written in TypeScript and has no WebAssembly or native binari
 was rewritten, the npm package shrank from 3 MB to about 120 kB, and it installs and runs on any platform Node.js
 supports (including Alpine/musl and bundled serverless functions).
 
+On JSR, `@matmen/imagescript` is now the same package as on npm (it used to be the Deno-only 1.x with WebAssembly),
+published from the TypeScript sources with every release: `deno add jsr:@matmen/imagescript`.
+
 ### Breaking changes
 
 - **Node.js 22.13 or newer is required.** The package is ES modules only; `require('imagescript')` keeps working
 
@@ -9,11 +9,12 @@
 
 **ImageScript** is a zero-dependency alternative to common JavaScript bitmap image manipulation tools. Every codec and
 renderer is written in TypeScript: no WebAssembly, no native binaries, no npm dependencies, no install scripts. The
-package is about 120 kB (compressed) and runs anywhere Node.js 22.13 or newer runs, including Alpine/musl, ARM and bundled
-serverless functions. It works with both `import` and `require()`, type definitions are included.
+package is about 120 kB (compressed) and runs in Node.js 22.13 or newer (including Alpine/musl, ARM and bundled
+serverless functions), Deno, Bun and browsers. It works with both `import` and `require()`, type definitions are included.
 
 ```sh
-npm install imagescript
+npm install imagescript              # Node.js, Bun and bundlers
+deno add jsr:@matmen/imagescript     # Deno (npm:imagescript works too)
 ```
 
 ---
 
@@ -0,0 +1,9 @@
+{
+  "name": "@matmen/imagescript",
+  "version": "3.0.0",
+  "license": "(AGPL-3.0-or-later OR MIT)",
+  "exports": "./src/index.ts",
+  "publish": {
+    "include": ["src", "README.md", "LICENSE", "LICENSE.MIT", "LICENSE.AGPL-3.0"]
+  }
+}
@@ -25,7 +25,7 @@
     "docs": "node scripts/docs.js",
     "test": "npm run build && node ./tests/run.js",
     "prepack": "npm run build",
-    "version": "node scripts/build.js && git add src/version.ts"
+    "version": "node scripts/build.js && git add src/version.ts jsr.json"
   },
   "repository": {
     "type": "git",
 
@@ -11,6 +11,10 @@ const run = args => execFileSync(process.execPath, [tsc, ...args], { cwd: root,
 // keep the version reported in PNG metadata in sync with package.json
 const { version } = require('../package.json');
 fs.writeFileSync(path.join(root, 'src/version.ts'), `// kept in sync with package.json by scripts/build.js\nexport const VERSION = '${version}';\n`);
+// and the one JSR publishes
+const jsrPath = path.join(root, 'jsr.json');
+const jsr = JSON.parse(fs.readFileSync(jsrPath, 'utf8'));
+if (jsr.version !== version) fs.writeFileSync(jsrPath, JSON.stringify({ ...jsr, version }, null, 2) + '\n');
 
 fs.rmSync(path.join(root, 'dist'), { recursive: true, force: true });
 // declarations keep the doc comments (editors show them), the JavaScript doesn't need them
 
@@ -1,12 +1,13 @@
-// checks a GitHub release before it is published to npm, run by .github/workflows/release.yml:
-// the tag matches package.json, the version is valid semver, newer than what npm has and listed in the changelog,
-// prereleases are marked as such. Prints the npm dist-tag to publish under (and writes it to GITHUB_OUTPUT)
+// checks a GitHub release before it is published to npm and JSR, run by .github/workflows/release.yml:
+// the tag matches package.json and jsr.json, the version is valid semver, newer than what npm has, not on JSR yet and
+// listed in the changelog, prereleases are marked as such. Prints the npm dist-tag to publish under (and writes it to GITHUB_OUTPUT)
 // usage: node scripts/release-check.js <tag> [prerelease flag of the GitHub release: true/false]
 const fs = require('fs');
 const path = require('path');
 
 const root = path.join(__dirname, '..');
 const { name, version } = require('../package.json');
+const jsr = require('../jsr.json');
 const [tag = '', prereleaseFlag = 'false'] = process.argv.slice(2);
 
 const errors = [];
@@ -50,6 +51,8 @@ async function main() {
         fail(current.pre.length ? `${version} is a prerelease version, mark the GitHub release as prerelease`
             : `the GitHub release is marked as prerelease, but ${version} has no prerelease suffix (like -beta.1)`);
 
+    if (jsr.version !== version) fail(`jsr.json has version ${jsr.version}, package.json ${version} (npm run build syncs them)`);
+
     const changelog = fs.readFileSync(path.join(root, 'CHANGELOG.md'), 'utf8');
     if (!changelog.split('\n').some(line => /^##\s/.test(line) && line.replace(/^##\s+v?/, '').trim().split(/\s/)[0] === version))
         fail(`CHANGELOG.md has no "## ${version}" section`);
@@ -83,6 +86,12 @@ async function main() {
         else if (latest && compare(current, latest) < 0) distTag = `v${current.major}-latest`;
     }
 
+    // JSR has no dist-tags, its "latest" is the newest stable version
+    const [scope, jsrName] = jsr.name.slice(1).split('/');
+    const jsrRes = await fetch(`https://api.jsr.io/scopes/${scope}/packages/${jsrName}/versions/${encodeURIComponent(version)}`);
+    if (jsrRes.ok) fail(`${jsr.name}@${version} is already published on JSR`);
+    else if (jsrRes.status !== 404) throw new Error(`JSR answered ${jsrRes.status}`);
+
     if (errors.length) {
         for (const e of errors) console.error(`::error::${e}`);
         process.exit(1);