diff --git a/examples/negative.js b/examples/negative.js
index e0d0fd8..f6f5c3b 100755
--- a/examples/negative.js
+++ b/examples/negative.js
@@ -1,5 +1,4 @@
 #!/usr/bin/env node
-var sys = require('sys');
 var Traverse = require('traverse');
 
 var fixed = Traverse([
@@ -7,7 +6,8 @@ var fixed = Traverse([
 ]).modify(function (x) {
     if (x < 0) this.update(x + 128);
 }).get()
-sys.puts(sys.inspect(fixed));
+
+console.dir(fixed);
 
 /* Output:
     [ 5, 6, 125, [ 7, 8, 126, 1 ], { f: 10, g: 115 } ]
diff --git a/examples/stringify.js b/examples/stringify.js
index a9a0b2f..0cef7ec 100755
--- a/examples/stringify.js
+++ b/examples/stringify.js
@@ -1,6 +1,5 @@
 #!/usr/bin/env node
 var Traverse = require('traverse');
-var sys = require('sys');
 
 var obj = [ 'five', 6, -3, [ 7, 8, -2, 1 ], { f : 10, g : -13 } ];
 
diff --git a/index.js b/index.js
new file mode 100644
index 0000000..756830d
--- /dev/null
+++ b/index.js
@@ -0,0 +1,153 @@
+module.exports = Traverse;
+function Traverse (obj) {
+    if (!(this instanceof Traverse)) return new Traverse(obj);
+    this.value = obj;
+}
+
+Traverse.prototype.map = function (cb) {
+    var obj = Traverse.clone(this.value);
+    walk(obj, cb);
+    return obj;
+};
+
+Traverse.prototype.forEach = function (cb) {
+    walk(this.value, cb);
+    return this.value;
+};
+
+Traverse.prototype.paths = function () {
+    var acc = [];
+    this.forEach(function (x) {
+        acc.push(this.path); 
+    });
+    return acc;
+};
+
+Traverse.prototype.nodes = function () {
+    var acc = [];
+    this.forEach(function (x) {
+        acc.push(this.node);
+    });
+    return acc;
+};
+
+Traverse.prototype.clone = function () {
+    // clone refObj for a properly immutable interface:
+    var refs = [];
+    var nodes = [];
+    
+    return (function clone (ref) {
+        if (typeof ref == 'object' && ref !== null) {
+            var node = Array.isArray(ref) ? [] : {};
+            refs.push(ref);
+            nodes.push(node);
+            
+            Object.keys(ref).forEach(function (key) {
+                var i = refs.indexOf(ref[key]);
+                if (i >= 0) {
+                    node[key] = nodes[i];
+                }
+                else {
+                    node[key] = clone(ref[key]);
+                }
+                
+            });
+            
+            refs.pop();
+            nodes.pop();
+            
+            // To make instanceof work:
+            if (!Array.isArray(ref)) node.__proto__ = ref.__proto__;
+            
+            // Probably there are other attributes worth copying
+            return node;
+        }
+        else {
+            return ref;
+        }
+    })(this.value);
+};
+
+function walk (root, cb) {
+    var path = [];
+    var parents = [];
+    
+    return (function walker (node) {
+        var modifiers = {};
+        
+        var state = {
+            node : node,
+            path : [].concat(path),
+            parent : parents.slice(-1)[0],
+            key : path.slice(-1)[0],
+            isRoot : node === root,
+            level : path.length,
+            circular : null,
+            update : function (x) {
+                if (state.isRoot) {
+                    root = x;
+                }
+                else {
+                    state.parent.node[state.key] = x;
+                }
+                state.node = x;
+            },
+            before : function (f) { modifiers.before = f },
+            after : function (f) { modifiers.after = f },
+            pre : function (f) { modifiers.pre = f },
+            post : function (f) { modifiers.post = f }
+        };
+        
+        if (typeof node == 'object' && node !== null) {
+            state.isLeaf = Object.keys(node).length == 0
+            var circs = parents.filter(function (p) {
+                return node == p.node
+            });
+            if (circs.length) state.circular = circs[0];
+        }
+        else {
+            state.isLeaf = true;
+        }
+        
+        state.notLeaf = !state.isLeaf;
+        state.notRoot = !state.isRoot;
+        
+        // use return values to update if defined
+        var ret = cb.call(state, node);
+        if (ret !== undefined && state.update) state.update(ret);
+        if (modifiers.before) modifiers.before.call(state, state.node);
+        
+        if (typeof state.node == 'object'
+        && state.node !== null && !state.circular) {
+            parents.push(state);
+            
+            var keys = Object.keys(state.node);
+            keys.forEach(function (key, i) {
+                path.push(key);
+                
+                if (modifiers.pre) modifiers.pre.call(state, state.node[key], key);
+                
+                var child = walker(state.node[key]);
+                child.isLast = i == keys.length - 1;
+                child.isFirst = i == 0;
+                
+                if (modifiers.post) modifiers.post.call(state, child);
+                
+                path.pop();
+            });
+            parents.pop();
+        }
+        
+        if (modifiers.after) modifiers.after.call(state, state.node);
+        
+        return state;
+    })(root);
+}
+
+Object.keys(Traverse.prototype).forEach(function (key) {
+    Traverse[key] = function (obj) {
+        var args = [].slice.call(arguments, 1);
+        var t = Traverse(obj);
+        return t[key].apply(t, args);
+    };
+});
diff --git a/lib/hash.js b/lib/hash.js
deleted file mode 100644
index ed2b8be..0000000
--- a/lib/hash.js
+++ /dev/null
@@ -1,218 +0,0 @@
-module.exports = Hash;
-var Traverse = require('traverse');
-
-function Hash (hash, xs) {
-    if (Array.isArray(hash) && Array.isArray(xs)) {
-        var to = Math.min(hash.length, xs.length);
-        var acc = {};
-        for (var i = 0; i < to; i++) {
-            acc[hash[i]] = xs[i];
-        }
-        return Hash(acc);
-    }
-    
-    if (hash === undefined) return Hash({});
-    
-    var self = {
-        map : function (f) {
-            var acc = { __proto__ : hash.__proto__ };
-            Object.keys(hash).forEach(function (key) {
-                acc[key] = f.call(self, hash[key], key);
-            });
-            return Hash(acc);
-        },
-        forEach : function (f) {
-            Object.keys(hash).forEach(function (key) {
-                f.call(self, hash[key], key);
-            });
-            return self;
-        },
-        filter : function (f) {
-            var acc = { __proto__ : hash.__proto__ };
-            Object.keys(hash).forEach(function (key) {
-                if (f.call(self, hash[key], key)) {
-                    acc[key] = hash[key];
-                }
-            });
-            return Hash(acc);
-        },
-        detect : function (f) {
-            for (var key in hash) {
-                if (f.call(self, hash[key], key)) {
-                    return hash[key];
-                }
-            }
-            return undefined;
-        },
-        reduce : function (f, acc) {
-            var keys = Object.keys(hash);
-            if (acc === undefined) acc = keys.shift();
-            keys.forEach(function (key) {
-                acc = f.call(self, acc, hash[key], key);
-            });
-            return acc;
-        },
-        some : function (f) {
-            for (var key in hash) {
-                if (f.call(self, hash[key], key)) return true;
-            }
-            return false;
-        },
-        update : function (h) {
-            Object.keys(h).forEach(function (key) {
-                hash[key] = h[key];
-            });
-            return self;
-        },
-        merge : function (h) {
-            return self.copy.update(h);
-        },
-        has : function (key) { // only operates on enumerables
-            return Array.isArray(key)
-                ? key.every(function (k) { return self.has(k) })
-                : self.keys.indexOf(key.toString()) >= 0;
-        },
-        valuesAt : function (keys) {
-            return Array.isArray(keys)
-                ? keys.map(function (key) { return hash[key] })
-                : hash[keys]
-            ;
-        },
-        tap : function (f) {
-            f.call(self, hash);
-            return self;
-        },
-        extract : function (keys) {
-            var acc = {};
-            keys.forEach(function (key) {
-                acc[key] = hash[key];
-            });
-            return Hash(acc);
-        },
-        exclude : function (keys) {
-            return self.filter(function (_, key) {
-                return keys.indexOf(key) < 0
-            });
-        },
-        end : hash,
-        items : hash
-    };
-    
-    var props = {
-        keys : function () { return Object.keys(hash) },
-        values : function () {
-            return Object.keys(hash).map(function (key) { return hash[key] });
-        },
-        compact : function () {
-            return self.filter(function (x) { return x !== undefined });
-        },
-        clone : function () { return Hash(Hash.clone(hash)) },
-        copy : function () { return Hash(Hash.copy(hash)) },
-        length : function () { return Object.keys(hash).length },
-        size : function () { return self.length }
-    };
-    
-    if (self.__defineGetter__) {
-        for (var key in props) {
-            self.__defineGetter__(key, props[key]);
-        }
-    }
-    else if (Object.defineProperty) {
-        for (var key in props) {
-            Object.defineProperty(self, key, { get : props[key] });
-        }
-    }
-    else {
-        // non-lazy version for browsers that suck >_<
-        for (var key in props) {
-            self[key] = prop();
-        }
-    }
-    
-    return self;
-};
-
-// deep copy
-Hash.clone = function (ref) {
-    return Traverse.clone(ref);
-};
-
-// shallow copy
-Hash.copy = function (ref) {
-    var hash = { __proto__ : ref.__proto__ };
-    Object.keys(ref).forEach(function (key) {
-        hash[key] = ref[key];
-    });
-    return hash;
-};
-
-Hash.map = function (ref, f) {
-    return Hash(ref).map(f).items;
-};
-
-Hash.forEach = function (ref, f) {
-    Hash(ref).forEach(f);
-};
-
-Hash.filter = function (ref, f) {
-    return Hash(ref).filter(f).items;
-};
-
-Hash.detect = function (ref, f) {
-    return Hash(ref).detect(f);
-};
-
-Hash.reduce = function (ref, f, acc) {
-    return Hash(ref).reduce(f, acc);
-};
-
-Hash.some = function (ref, f) {
-    return Hash(ref).some(f);
-};
-
-Hash.update = function (a, b) {
-    return Hash(a).update(b).items;
-};
-
-Hash.merge = function (a, b) {
-    return Hash(a).merge(b).items;
-};
-
-Hash.has = function (ref, key) {
-    return Hash(ref).has(key);
-};
-
-Hash.valuesAt = function (ref, keys) {
-    return Hash(ref).valuesAt(keys);
-};
-
-Hash.tap = function (ref, f) {
-    return Hash(ref).tap(f).items;
-};
-
-Hash.extract = function (ref, keys) {
-    return Hash(ref).extract(keys).items;
-};
-
-Hash.exclude = function (ref, keys) {
-    return Hash(ref).exclude(keys).items;
-};
-
-Hash.concat = function (xs) {
-    var hash = Hash({});
-    xs.forEach(function (x) { hash.update(x) });
-    return hash.items;
-};
-
-Hash.zip = function (xs, ys) {
-    return Hash(xs, ys).items;
-};
-
-// .length is already defined for function prototypes
-Hash.size = function (ref) {
-    return Hash(ref).size;
-};
-
-Hash.compact = function (ref) {
-    return Hash(ref).compact.items;
-};
diff --git a/lib/traverse.js b/lib/traverse.js
deleted file mode 100644
index 614d94e..0000000
--- a/lib/traverse.js
+++ /dev/null
@@ -1,183 +0,0 @@
-module.exports = Traverse;
-module.exports.Traverse = Traverse;
-
-function Traverse (refObj) {
-    if (!(this instanceof Traverse)) return new Traverse(refObj);
-    
-    // clone refObj for a properly immutable interface:
-    clone.refs = [];
-    clone.nodes = [];
-    function clone(ref) {
-        if (typeof ref == 'object' && ref !== null) {
-            var node = Array.isArray(ref) ? [] : {};
-            clone.refs.push(ref);
-            clone.nodes.push(node);
-            
-            Object.keys(ref).forEach(function (key) {
-                var i = clone.refs.indexOf(ref[key]);
-                if (i >= 0) {
-                    node[key] = clone.nodes[i];
-                }
-                else {
-                    node[key] = clone(ref[key]);
-                }
-                
-            });
-            
-            clone.refs.pop();
-            clone.nodes.pop();
-            
-            // To make instanceof work:
-            if (!Array.isArray(ref)) node.__proto__ = ref.__proto__;
-            
-            // Probably there are other attributes worth copying
-            return node;
-        }
-        else {
-            return ref;
-        }
-    }
-    this.value = clone(refObj);
-    
-    // get() is deprecated, use .value
-    this.get = function () { return this.value };
-    
-    this.map = function (cb) {
-        walk({
-            node : this.value,
-            root : this.value,
-            callback : cb
-        });
-        return this;
-        
-    };
-    
-    this.modify = this.map; // deprecated .modify()
-    
-    this.forEach = function (f) {
-        this.map(function (node) {
-            delete this.update;
-            f.call(this, node);
-        });
-        return this;
-    };
-    
-    this.paths = function () {
-        var acc = [];
-        this.forEach(function (x) {
-            acc.push(this.path); 
-        });
-        return acc;
-    };
-    
-    this.nodes = function () {
-        var acc = [];
-        this.forEach(function (x) {
-            acc.push(this.node);
-        });
-        return acc;
-    };
-}
-
-Traverse.clone = function (obj) {
-    return Traverse(obj).get();
-};
-
-Traverse.map = function (obj, f) {
-    return Traverse(obj).map(f).get();
-};
-
-Traverse.forEach = function (obj, f) {
-    Traverse(obj).forEach(f);
-};
-
-Traverse.paths = function (obj) {
-    return Traverse(obj).paths();
-};
-
-Traverse.nodes = function (obj) {
-    return Traverse(obj).nodes();
-};
-
-function walk (params) {
-    var node = params.node;
-    var root = params.root;
-    var path = params.path || [];
-    var parents = params.parents || [];
-    var cb = params.callback;
-    
-    var modifiers = {};
-    
-    var state = {
-        node : node,
-        path : [].concat(path),
-        parent : parents.slice(-1)[0],
-        key : path.slice(-1)[0],
-        isRoot : node === root,
-        level : path.length,
-        circular : null,
-        update : function (x) {
-            if (state.isRoot) {
-                root = x;
-            }
-            else {
-                state.parent.node[state.key] = x;
-            }
-            state.node = x;
-        },
-        before : function (f) { modifiers.before = f },
-        after : function (f) { modifiers.after = f },
-        pre : function (f) { modifiers.pre = f },
-        post : function (f) { modifiers.post = f }
-    };
-    
-    if (typeof node == 'object' && node !== null) {
-        state.isLeaf = Object.keys(node).length == 0
-        var circs = parents.filter(function (p) {
-            return node == p.node
-        });
-        if (circs.length) state.circular = circs[0];
-    }
-    else {
-        state.isLeaf = true;
-    }
-    
-    state.notLeaf = !state.isLeaf;
-    state.notRoot = !state.isRoot;
-    
-    // use return values to update if defined
-    var ret = cb.call(state, node);
-    if (ret !== undefined && state.update) state.update(ret);
-    if (modifiers.before) modifiers.before.call(state, state.node);
-    
-    if (typeof state.node == 'object'
-    && state.node !== null && !state.circular) {
-        parents.push(state);
-        
-        var keys = Object.keys(state.node);
-        keys.forEach(function (key, i) {
-            path.push(key);
-            
-            if (modifiers.pre) modifiers.pre.call(state, state.node[key], key);
-            
-            var child = walk({
-                node : state.node[key],
-                root : root,
-                path : path,
-                parents : parents,
-                callback : cb
-            });
-            child.isLast = i == keys.length - 1;
-            child.isFirst = i == 0;
-            
-            if (modifiers.post) modifiers.post.call(state, child);
-            
-            path.pop();
-        });
-        parents.pop();
-    }
-    
-    if (modifiers.after) modifiers.after.call(state, state.node);
-    
-    return state;
-}
diff --git a/lib/web.js b/lib/web.js
deleted file mode 100644
index 93fe52d..0000000
--- a/lib/web.js
+++ /dev/null
@@ -1,15 +0,0 @@
-var fs = require('fs');
-
-// return a special webified version of traverse
-exports.source = function () {
-    return [ 'traverse.js', 'hash.js' ].map(scrub).join('\n');
-};
-
-function scrub (filename) {
-    return fs.readFileSync(__dirname + '/' + filename)
-        .toString()
-        .replace(/^module\..*/mg, '')
-        .replace(/^var \S+\s*=\s*require\(.*\);/mg, '')
-    ;
-}
-
diff --git a/package.json b/package.json
index 2ec52d0..8dbaaee 100644
--- a/package.json
+++ b/package.json
@@ -1,16 +1,23 @@
 {
     "name" : "traverse",
-    "version" : "0.2.4",
+    "version" : "0.3.0",
     "description" : "Traverse and transform objects by visiting every node on a recursive walk.",
     "author" : "James Halliday",
     "license" : "MIT/X11",
+    "main" : "./index",
     "modules" : {
-        "index" : "./lib/traverse",
         "web" : "./lib/web",
         "hash" : "./lib/hash"
     },
     "repository" : {
         "type" : "git",
         "url" : "http://github.com/substack/js-traverse.git"
+    },
+    "devDependencies" : {
+        "seq" : ">=0.1.7",
+        "expresso" : ">=0.6.0"
+    },
+    "scripts" : {
+        "test" : "expresso"
     }
 }
diff --git a/test/hash.js b/test/hash.js
old mode 100755
new mode 100644
diff --git a/test/instance.js b/test/instance.js
old mode 100755
new mode 100644
diff --git a/test/interface.js b/test/interface.js
old mode 100755
new mode 100644
diff --git a/test/json.js b/test/json.js
old mode 100755
new mode 100644
diff --git a/test/leaves.js b/test/leaves.js
old mode 100755
new mode 100644
diff --git a/test/negative.js b/test/negative.js
old mode 100755
new mode 100644
diff --git a/test/obj.js b/test/obj.js
old mode 100755
new mode 100644
diff --git a/test/stringify.js b/test/stringify.js
old mode 100755
new mode 100644