diff --git a/.gitignore b/.gitignore
index c44e8809..07802af0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,8 +5,10 @@
 
 # Ignore TypeScript-emitted files
 *.js
+*.js.map
 *.swp
 !.*rc.js
 *.d.ts
+dist/
 # Except...
 !/types/**/*.d.ts
diff --git a/package.json b/package.json
index 055d6420..c17e6b8a 100644
--- a/package.json
+++ b/package.json
@@ -19,18 +19,38 @@
     "url": "git://github.com/coderaiser/recast.git"
   },
   "license": "MIT",
-  "main": "main.js",
+  "main": "./dist/src/main.js",
   "types": "main.d.ts",
   "scripts": {
-    "mocha": "test/run.sh",
-    "debug": "test/run.sh --inspect-brk",
-    "test": "npm run lint && npm run build && npm run mocha",
-    "build": "npm run clean && tsc",
+    "test": "jest",
+    "watch": "jest --watch",
+    "snapupdate": "jest --updateSnapshot",
+    "build": "npm run clean && npm run compile",
     "lint": "eslint --ext .ts .",
     "format": "prettier --write '{lib,test}/**.ts' '*rc.js'",
-    "clean": "ts-emit-clean",
-    "prepack": "npm run build",
-    "postpack": "npm run clean"
+    "clean": "rimraf ./dist",
+    "compile": "tsc -p .",
+    "prepack": "npm run build"
+  },
+  "jest": {
+    "testEnvironment": "node",
+    "roots": [
+      "./test"
+    ],
+    "testMatch": [
+      "**/test/**/*\\.[jt]s?(x)",
+      "**/run\\.[jt]s"
+    ],
+    "transform": {
+      "^.+\\.ts$": "ts-jest"
+    },
+    "testPathIgnorePatterns": ["<rootDir>/test/data/"],
+    "moduleFileExtensions": [
+      "ts",
+      "js",
+      "json",
+      "node"
+    ]
   },
   "lint-staged": {
     "*.ts": [
@@ -53,18 +73,22 @@
     "@babel/preset-env": "7.11.5",
     "@types/esprima": "4.0.2",
     "@types/glob": "7.1.3",
-    "@types/mocha": "8.0.3",
+    "@types/jest": "^27.4.1",
     "@types/node": "^16.0.0",
     "@typescript-eslint/parser": "^5.8.0",
     "eslint": "^8.5.0",
     "esprima-fb": "15001.1001.0-dev-harmony-fb",
+    "expect": "^27.5.1",
+    "jest": "^27.5.1",
+    "jest-mock": "^27.5.1",
     "flow-parser": "^0.159.0",
     "glob": "^7.1.7",
     "lint-staged": "^10.2.6",
-    "mocha": "^9.0.2",
     "prettier": "^2.0.5",
+    "rimraf": "^3.0.2",
     "reify": "0.20.12",
-    "ts-emit-clean": "1.0.0",
+    "ts-jest": "^27.1.4",
+    "ts-node": "^10.7.0",
     "typescript": "^4.3.5"
   },
   "engines": {
diff --git a/test/lines.ts b/test/lines.ts
index 61446a04..95c6a5e1 100644
--- a/test/lines.ts
+++ b/test/lines.ts
@@ -491,7 +491,7 @@ describe("lines", function () {
 
     fs.readFile(__filename, "utf-8", function (err, source) {
       assert.equal(err, null);
-      assert.strictEqual(fromString(source).guessTabWidth(), 4);
+      assert.strictEqual(fromString(source).guessTabWidth(), 2);
 
       fs.readFile(
         path.join(__dirname, "..", "package.json"),
diff --git a/test/perf.ts b/test/perf.ts
index 566c26cb..49660ccc 100644
--- a/test/perf.ts
+++ b/test/perf.ts
@@ -2,31 +2,35 @@ import path from "path";
 import fs from "fs";
 import * as recast from "../main";
 
-const source = fs.readFileSync(
-  path.join(__dirname, "data", "backbone.js"),
-  "utf8",
-);
-
-const start = +new Date();
-const ast = recast.parse(source);
-const types = Object.create(null);
-
-const parseTime = +new Date() - start;
-console.log("parse", parseTime, "ms");
-
-recast.visit(ast, {
-  visitNode: function (path) {
-    types[path.value.type] = true;
-    this.traverse(path);
-  },
-});
-
-const visitTime = +new Date() - start - parseTime;
-console.log("visit", visitTime, "ms");
-
-recast.prettyPrint(ast).code;
-
-const printTime = +new Date() - start - visitTime - parseTime;
-console.log("print", printTime, "ms");
-
-console.log("total", +new Date() - start, "ms");
+describe('performance metrics', () => {
+  it('should print out', () => {
+    const source = fs.readFileSync(
+      path.join(__dirname, "data", "backbone.js"),
+      "utf8",
+    );
+    
+    const start = +new Date();
+    const ast = recast.parse(source);
+    const types = Object.create(null);
+    
+    const parseTime = +new Date() - start;
+    console.log("parse", parseTime, "ms");
+    
+    recast.visit(ast, {
+      visitNode: function (path) {
+        types[path.value.type] = true;
+        this.traverse(path);
+      },
+    });
+    
+    const visitTime = +new Date() - start - parseTime;
+    console.log("visit", visitTime, "ms");
+    
+    recast.prettyPrint(ast).code;
+    
+    const printTime = +new Date() - start - visitTime - parseTime;
+    console.log("print", printTime, "ms");
+    
+    console.log("total", +new Date() - start, "ms");
+  });
+})
diff --git a/test/typescript.ts b/test/typescript.ts
index 53514acc..54a5a76b 100644
--- a/test/typescript.ts
+++ b/test/typescript.ts
@@ -449,7 +449,7 @@ function testReprinting(pattern: any, description: any) {
             return;
           }
 
-          this.timeout(20000);
+          jest.setTimeout(20000);
 
           assert.strictEqual(recast.print(ast).code, source);
           const reprintedCode = recast.prettyPrint(ast).code;
diff --git a/tsconfig.json b/tsconfig.json
index b11175ee..cc2b16dc 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -4,7 +4,9 @@
     "lib": ["es2015"],
     "module": "commonjs",
     "declaration": true,
+    "declarationMap": true,
     "rootDir": ".",
+    "outDir": "dist",
     "strict": true,
     "noUnusedLocals": true,
     "noUnusedParameters": true,
@@ -12,6 +14,7 @@
     "moduleResolution": "node",
     "esModuleInterop": true,
     "importHelpers": true,
+    "sourceMap": true,
     "stripInternal": true
   },
   "exclude": [