@@ -20,6 +20,7 @@
   "devDependencies": {
     "@aklinker1/check": "^2.1.0",
     "@types/bun": "latest",
+    "changelogen": "^0.6.2",
     "elysia": "^1.3.5",
     "expect-type": "^1.2.1",
     "hono": "^4.8.3",
 
@@ -1,11 +1,14 @@
 import { version as oldPkgVersion } from "../package.json" with { type: "json" };
 import { version as oldJsrVersion } from "../jsr.json" with { type: "json" };
-
-const newVersion = process.argv[2];
-if (!newVersion) {
-  console.error("Usage: bun run scripts/publish.ts <new_version>");
-  process.exit(1);
-}
+import {
+  loadChangelogConfig,
+  getGitDiff,
+  generateMarkDown,
+  createGithubRelease,
+  parseChangelogMarkdown,
+  bumpVersion,
+  parseCommits,
+} from "changelogen";
 
 if (oldPkgVersion !== oldJsrVersion) {
   console.error(
@@ -29,34 +32,46 @@ if (currentBranch !== "main") {
   process.exit(1);
 }
 
-console.log("\nBumping version...", {
-  oldVersion,
-  newVersion,
-});
+console.log(`\nBumping version and generating changelog...`);
 
-function replaceVersion(
-  text: string,
-  oldVersion: string,
-  newVersion: string,
-): string {
-  return text.replace(
-    `"version": "${oldVersion}"`,
-    `"version": "${newVersion}"`,
-  );
+const changelogConfig = await loadChangelogConfig(process.cwd(), {});
+const commits = parseCommits(
+  await getGitDiff(changelogConfig.from),
+  changelogConfig,
+);
+const newVersion = await bumpVersion(commits, changelogConfig);
+if (!newVersion) {
+  console.error("Failed to bump version", { commits });
+  process.exit(1);
 }
 
-const pkgJsonContent = await Bun.file("package.json").text();
-const updatedPkgJsonContent = replaceVersion(
-  pkgJsonContent,
-  oldVersion,
-  newVersion,
+const md = await generateMarkDown(commits, changelogConfig);
+console.log(md);
+const changelog = parseChangelogMarkdown(
+  await Bun.file("CHANGELOG.md")
+    .text()
+    .catch(() => ""),
+);
+changelog.releases.unshift({
+  body: md,
+  version: newVersion,
+});
+await Bun.write(
+  "CHANGELOG.md",
+  `# Changelog\n\n${changelog.releases.map((release) => release.body).join("\n\n")}\n`,
 );
-await Bun.write("package.json", updatedPkgJsonContent);
+
+console.log(`Bumped version from ${oldVersion} to ${newVersion}`);
+
+// Manually update jsr.json to match the new version bumped by changelogen
+function replaceVersion(text: string, oldVer: string, newVer: string): string {
+  return text.replace(`"version": "${oldVer}"`, `"version": "${newVer}"`);
+}
 
 const jsrJsonContent = await Bun.file("jsr.json").text();
 const updatedJsrJsonContent = replaceVersion(
   jsrJsonContent,
-  oldVersion,
+  oldJsrVersion,
   newVersion,
 );
 await Bun.write("jsr.json", updatedJsrJsonContent);
@@ -66,21 +81,30 @@ const changedFiles = (await Bun.$`git diff --name-only`)
   .split("\n")
   .map((line) => line.trim())
   .filter((line) => line !== "");
-if (
-  changedFiles.length !== 2 ||
-  changedFiles[0] !== "jsr.json" ||
-  changedFiles[1] !== "package.json"
-) {
+console.log(changedFiles);
+
+const expectedFiles = ["CHANGELOG.md", "jsr.json", "package.json"].sort();
+const actualFiles = changedFiles.sort();
+
+if (JSON.stringify(actualFiles) !== JSON.stringify(expectedFiles)) {
   console.error(
-    "Missing required changes - jsr.json and package.json should be the only changed files.",
+    "Unexpected changed files after changelogen and jsr.json update.",
+    "Expected:",
+    expectedFiles,
+    "Actual:",
+    actualFiles,
   );
   await Bun.$`git status`;
   process.exit(1);
 }
 
-await Bun.$`git add jsr.json package.json`;
+await Bun.$`git add jsr.json package.json CHANGELOG.md`;
 await Bun.$`git commit -m "chore(release): v${newVersion}"`;
 await Bun.$`git tag v${newVersion}`;
 await Bun.$`git push origin main`;
 await Bun.$`git push --tags`;
+await createGithubRelease(changelogConfig, {
+  tag_name: `v${newVersion}`,
+  body: md,
+});
 await Bun.$`bun jsr publish`;