share · ericyhwang · Apr 17, 2026 · Apr 8, 2026 · Apr 8, 2026 · Apr 8, 2026
diff --git a/.gitignore b/.gitignore
@@ -36,6 +36,9 @@ node_modules
 package-lock.json
 jspm_packages
 
+# TypeScript output
+lib/
+
 # Don't commit generated JS bundles
 examples/**/static/dist/bundle.js
 examples/**/dist
diff --git a/eslint.config.js b/eslint.config.js
@@ -1,9 +1,10 @@
-const js = require("@eslint/js");
+const jsEslint = require("@eslint/js");
 const {
     defineConfig,
     globalIgnores,
 } = require("eslint/config");
 const eslintConfigGoogle = require('eslint-config-google');
+const tsEslint = require('typescript-eslint');
 
 // The ESLint ecmaVersion argument is inconsistently used. Some rules will ignore it entirely, so if the rule has
 // been set, it will still error even if it's not applicable to that version number. Since Google sets these
@@ -54,6 +55,7 @@ var SHAREDB_RULES = {
 module.exports = defineConfig([
     {
         extends: [eslintConfigGoogle],
+        files: ["**/*.js"],
         ignores: ['eslint.config.js'],
 
         languageOptions: {
@@ -67,6 +69,13 @@ module.exports = defineConfig([
 
         rules: Object.assign({}, DISABLED_ES6_OPTIONS, SHAREDB_RULES),
     },
+    {
+        extends: [
+            jsEslint.configs.recommended,
+            tsEslint.configs.recommended,
+        ],
+        files: ["**/*.ts"],
+    },
     globalIgnores(["docs/"]),
     {
         files: ["examples/counter-json1-vite/*.js"],

diff --git a/package.json b/package.json
@@ -12,6 +12,7 @@
   },
   "devDependencies": {
     "@eslint/js": "^10.0.1",
+    "@types/node": "^24.12.0",
     "chai": "^6.2.2",
     "eslint": "^10.1.0",
     "eslint-config-google": "^0.14.0",
@@ -22,7 +23,9 @@
     "rich-text": "^4.1.0",
     "sharedb-legacy": "npm:sharedb@1.1.0",
     "sinon": "^21.0.3",
-    "sinon-chai": "^4.0.1"
+    "sinon-chai": "^4.0.1",
+    "typescript": "~6.0.2",
+    "typescript-eslint": "^8.58.0"
   },
   "files": [
     "lib/",

diff --git a/lib/agent.js → src/agent.ts b/lib/agent.js → src/agent.ts
diff --git a/lib/backend.js → src/backend.ts b/lib/backend.js → src/backend.ts
diff --git a/lib/client/connection.js → src/client/connection.ts b/lib/client/connection.js → src/client/connection.ts
diff --git a/lib/client/doc.js → src/client/doc.ts b/lib/client/doc.js → src/client/doc.ts
diff --git a/lib/client/index.js → src/client/index.ts b/lib/client/index.js → src/client/index.ts
diff --git a/lib/client/presence/doc-presence-emitter.js → src/client/presence/doc-presence-emitter.ts b/lib/client/presence/doc-presence-emitter.js → src/client/presence/doc-presence-emitter.ts
diff --git a/lib/client/presence/doc-presence.js → src/client/presence/doc-presence.ts b/lib/client/presence/doc-presence.js → src/client/presence/doc-presence.ts
diff --git a/lib/client/presence/local-doc-presence.js → src/client/presence/local-doc-presence.ts b/lib/client/presence/local-doc-presence.js → src/client/presence/local-doc-presence.ts
diff --git a/lib/client/presence/local-presence.js → src/client/presence/local-presence.ts b/lib/client/presence/local-presence.js → src/client/presence/local-presence.ts
diff --git a/lib/client/presence/presence.js → src/client/presence/presence.ts b/lib/client/presence/presence.js → src/client/presence/presence.ts
diff --git a/lib/client/presence/remote-doc-presence.js → src/client/presence/remote-doc-presence.ts b/lib/client/presence/remote-doc-presence.js → src/client/presence/remote-doc-presence.ts
diff --git a/lib/client/presence/remote-presence.js → src/client/presence/remote-presence.ts b/lib/client/presence/remote-presence.js → src/client/presence/remote-presence.ts
diff --git a/lib/client/query.js → src/client/query.ts b/lib/client/query.js → src/client/query.ts
diff --git a/...ient/snapshot-request/snapshot-request.js → ...ient/snapshot-request/snapshot-request.ts b/...ient/snapshot-request/snapshot-request.js → ...ient/snapshot-request/snapshot-request.ts
diff --git a/...hot-request/snapshot-timestamp-request.js → ...hot-request/snapshot-timestamp-request.ts b/...hot-request/snapshot-timestamp-request.js → ...hot-request/snapshot-timestamp-request.ts
diff --git a/...pshot-request/snapshot-version-request.js → ...pshot-request/snapshot-version-request.ts b/...pshot-request/snapshot-version-request.js → ...pshot-request/snapshot-version-request.ts
diff --git a/lib/db/index.js → src/db/index.ts b/lib/db/index.js → src/db/index.ts
diff --git a/lib/db/memory.js → src/db/memory.ts b/lib/db/memory.js → src/db/memory.ts
diff --git a/lib/emitter.js → src/emitter.ts b/lib/emitter.js → src/emitter.ts
diff --git a/lib/error.js → src/error.ts b/lib/error.js → src/error.ts
diff --git a/lib/index.js → src/index.ts b/lib/index.js → src/index.ts
diff --git a/lib/logger/index.js → src/logger/index.ts b/lib/logger/index.js → src/logger/index.ts
diff --git a/lib/logger/logger.js → src/logger/logger.ts b/lib/logger/logger.js → src/logger/logger.ts
diff --git a/lib/message-actions.js → src/message-actions.ts b/lib/message-actions.js → src/message-actions.ts
diff --git a/lib/milestone-db/index.js → src/milestone-db/index.ts b/lib/milestone-db/index.js → src/milestone-db/index.ts
diff --git a/lib/milestone-db/memory.js → src/milestone-db/memory.ts b/lib/milestone-db/memory.js → src/milestone-db/memory.ts
diff --git a/lib/milestone-db/no-op.js → src/milestone-db/no-op.ts b/lib/milestone-db/no-op.js → src/milestone-db/no-op.ts
diff --git a/lib/next-tick.js → src/next-tick.ts b/lib/next-tick.js → src/next-tick.ts
diff --git a/lib/op-stream.js → src/op-stream.ts b/lib/op-stream.js → src/op-stream.ts
diff --git a/lib/ot.js → src/ot.ts b/lib/ot.js → src/ot.ts
diff --git a/lib/projections.js → src/projections.ts b/lib/projections.js → src/projections.ts
diff --git a/lib/protocol.js → src/protocol.ts b/lib/protocol.js → src/protocol.ts
diff --git a/lib/pubsub/index.js → src/pubsub/index.ts b/lib/pubsub/index.js → src/pubsub/index.ts
diff --git a/lib/pubsub/memory.js → src/pubsub/memory.ts b/lib/pubsub/memory.js → src/pubsub/memory.ts
diff --git a/lib/query-emitter.js → src/query-emitter.ts b/lib/query-emitter.js → src/query-emitter.ts
diff --git a/lib/read-snapshots-request.js → src/read-snapshots-request.ts b/lib/read-snapshots-request.js → src/read-snapshots-request.ts
diff --git a/lib/snapshot.js → src/snapshot.ts b/lib/snapshot.js → src/snapshot.ts
diff --git a/lib/stream-socket.js → src/stream-socket.ts b/lib/stream-socket.js → src/stream-socket.ts
diff --git a/lib/submit-request.js → src/submit-request.ts b/lib/submit-request.js → src/submit-request.ts
diff --git a/lib/types.js → src/types.ts b/lib/types.js → src/types.ts
diff --git a/lib/util.js → src/util.ts b/lib/util.js → src/util.ts
diff --git a/tsconfig.json b/tsconfig.json
@@ -0,0 +1,21 @@
+{
+  "compilerOptions": {
+    "rootDir": "./src",
+    "outDir": "./lib",
+    "target": "ES5",
+    "module": "CommonJS",
+    "types": [
+      "node"
 var util = require('util'); 
 var EventEmitter = require('events').EventEmitter; 
 var util = require('util'); 
 var EventEmitter = require('events').EventEmitter; 
+    ],
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true,
+    "ignoreDeprecations": "6.0",
+    "noImplicitAny": false,
+    "noImplicitThis": false,
+  },
+  "include": [
+    "src/**/*.ts"
+  ],
+}