diff --git a/README.md b/README.md
index 85f11c4..3389501 100644
--- a/README.md
+++ b/README.md
@@ -29,6 +29,10 @@ inline annotations. If you want to come back when that's done, you can either
 watch/star this repo or follow me on
 [twitter](https://twitter.com/thejameskyle) for updates.
 
+### Tests
+
+Run with `node ./test/test.js`
+
 ---
 
 [![cc-by-4.0](https://licensebuttons.net/l/by/4.0/80x15.png)](http://creativecommons.org/licenses/by/4.0/)
diff --git a/test/test.js b/test/test.js
new file mode 100644
index 0000000..7fcfdda
--- /dev/null
+++ b/test/test.js
@@ -0,0 +1,101 @@
+var assert = require('assert');
+var superTinyCompiler = require('../super-tiny-compiler');
+
+var tokenizer = superTinyCompiler.tokenizer;
+var parser = superTinyCompiler.parser;
+var transformer = superTinyCompiler.transformer;
+var codeGenerator = superTinyCompiler.codeGenerator;
+var compiler = superTinyCompiler.compiler;
+
+var input = '(add 2 (subtract 4 2))';
+
+var tokens = [
+  { type: 'paren',  value: '('        },
+  { type: 'name',   value: 'add'      },
+  { type: 'number', value: '2'        },
+  { type: 'paren',  value: '('        },
+  { type: 'name',   value: 'subtract' },
+  { type: 'number', value: '4'        },
+  { type: 'number', value: '2'        },
+  { type: 'paren',  value: ')'        },
+  { type: 'paren',  value: ')'        }
+];
+
+//test tokenizer
+assert.deepStrictEqual(tokenizer(input), tokens);
+
+var ast = {
+  type: 'Program',
+  body: [{
+    type: 'CallExpression',
+    name: 'add',
+    params: [{
+      type: 'NumberLiteral',
+      value: '2'
+    }, {
+      type: 'CallExpression',
+      name: 'subtract',
+      params: [{
+        type: 'NumberLiteral',
+        value: '4'
+      }, {
+        type: 'NumberLiteral',
+        value: '2'
+      }]
+    }]
+  }]
+};
+
+// test parser/ast
+assert.deepStrictEqual(parser(tokens), ast);
+
+var newAst = {
+  "type": "Program",
+  "body": [
+    {
+      "type": "ExpressionStatement",
+      "expression": {
+        "type": "CallExpression",
+        "callee": {
+          "type": "Identifier",
+          "name": "add"
+        },
+        "arguments": [
+          {
+            "type": "NumberLiteral",
+            "value": "2"
+          },
+          {
+            "type": "CallExpression",
+            "callee": {
+              "type": "Identifier",
+              "name": "subtract"
+            },
+            "arguments": [
+              {
+                "type": "NumberLiteral",
+                "value": "4"
+              },
+              {
+                "type": "NumberLiteral",
+                "value": "2"
+              }
+            ]
+          }
+        ]
+      }
+    }
+  ]
+};
+
+assert.deepStrictEqual(transformer(ast), newAst);
+
+var output = 'add(2, subtract(4, 2));';
+
+// test generator
+assert.deepStrictEqual(codeGenerator(newAst), output);
+
+// test whole compiler
+assert.deepStrictEqual(compiler(input), output);
+
+console.log('All Passed!');