diff --git a/Makefile b/Makefile
index 46d169fdc..e71a74dc8 100644
--- a/Makefile
+++ b/Makefile
@@ -17,7 +17,7 @@ forcefull:
 	go install -a --tags=with_sqlite ./pkg/... ./server/... ./cmd/... ./third_party/... ./dev/...
 
 presubmit:
-	SKIP_DEP_TESTS=1 go test `pkg-config --libs sqlite3 1>/dev/null 2>/dev/null && echo "--tags=with_sqlite"` -short ./pkg/... ./server/camlistored ./server/appengine ./cmd/... ./dev/... && echo PASS
+	SKIP_DEP_TESTS=1 go test `pkg-config --libs sqlite3 1>/dev/null 2>/dev/null && echo "--tags=with_sqlite"` -short ./pkg/... ./server/camlistored/... ./server/appengine ./cmd/... ./dev/... && echo PASS
 
 embeds:
 	go install ./pkg/fileembed/genfileembed/ && genfileembed ./server/camlistored/ui && genfileembed ./pkg/server
diff --git a/pkg/misc/closure/gendeps.go b/pkg/misc/closure/gendeps.go
index 8b3624dcf..c4165560b 100644
--- a/pkg/misc/closure/gendeps.go
+++ b/pkg/misc/closure/gendeps.go
@@ -33,12 +33,18 @@ import (
 	"time"
 )
 
-// GenDeps returns the namespace dependencies between the
-// closure javascript files in root. It does not descend
-// in directories.
+// GenDeps returns the namespace dependencies between the closure javascript files in root. It does not descend in directories.
+// Each of the files listed in the output is prepended with the path "../../", which is assumed to be the location where these files can be found, relative to Closure's base.js.
+//
 // The format for each relevant javascript file is:
 // goog.addDependency("filepath", ["namespace provided"], ["required namespace 1", "required namespace 2", ...]);
 func GenDeps(root http.FileSystem) ([]byte, error) {
+	// In the typical configuration, Closure is served at 'closure/goog/...''
+	return GenDepsWithPath("../../", root)
+}
+
+// GenDepsWithPath is like GenDeps, but you can specify a path where the files are to be found at runtime relative to Closure's base.js.
+func GenDepsWithPath(pathPrefix string, root http.FileSystem) ([]byte, error) {
 	d, err := root.Open("/")
 	if err != nil {
 		return nil, fmt.Errorf("Failed to open root of %v: %v", root, err)
@@ -70,7 +76,7 @@ func GenDeps(root http.FileSystem) ([]byte, error) {
 			return nil, fmt.Errorf("Could not parse deps for %v: %v", name, err)
 		}
 		if len(prov) > 0 {
-			fmt.Fprintf(&buf, "goog.addDependency(%q, %v, %v);\n", "../../"+name, jsList(prov), jsList(req))
+			fmt.Fprintf(&buf, "goog.addDependency(%q, %v, %v);\n", pathPrefix+name, jsList(prov), jsList(req))
 		}
 	}
 	return buf.Bytes(), nil
diff --git a/pkg/misc/closure/jstest/jstest.go b/pkg/misc/closure/jstest/jstest.go
new file mode 100644
index 000000000..83e106925
--- /dev/null
+++ b/pkg/misc/closure/jstest/jstest.go
@@ -0,0 +1,121 @@
+/*
+Copyright 2014 The Camlistore Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package jstest uses the Go testing package to test JavaScript code using Node and Mocha.
+package jstest
+
+import (
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"camlistore.org/pkg/misc/closure"
+)
+
+// checkSystemRequirements checks whether system dependencies such as node and npm are present.
+func checkSystemRequirements() error {
+	binaries := []string{"mocha", "node", "npm"}
+	for _, b := range binaries {
+		if _, err := exec.LookPath(b); err != nil {
+			return fmt.Errorf("Required dependency %q not present", b)
+		}
+	}
+
+	c := exec.Command("npm", "list", "--depth=0")
+	b, _ := c.Output()
+	s := string(b)
+	modules := []string{"mocha", "assert"}
+	for _, m := range modules {
+		if !strings.Contains(s, fmt.Sprintf(" %s@", m)) {
+			return fmt.Errorf("Required npm module %v not present", m)
+		}
+	}
+	return nil
+}
+
+func getRepoRoot(target string) (string, error) {
+	dir, err := filepath.Abs(filepath.Dir(target))
+	if err != nil {
+		return "", fmt.Errorf("Could not get working directory: %v", err)
+	}
+	for ; dir != "" && filepath.Base(dir) != "camlistore.org"; dir = filepath.Dir(dir) {
+	}
+	if dir == "" {
+		return "", fmt.Errorf("Could not find Camlistore repo in ancestors of %q", target)
+	}
+	return dir, nil
+}
+
+// writeDeps runs closure.GenDeps() on targetDir and writes the resulting dependencies to a temporary file which will be used during the test run. The entries in the deps files are generated with paths relative to baseJS, which should be Closure's base.js file.
+func writeDeps(baseJS, targetDir string) (string, error) {
+	closureBaseDir := filepath.Dir(baseJS)
+	depPrefix, err := filepath.Rel(closureBaseDir, targetDir)
+	if err != nil {
+		return "", fmt.Errorf("Could not compute relative path from %q to %q: %v", baseJS, targetDir, err)
+	}
+
+	depPrefix += string(os.PathSeparator)
+	b, err := closure.GenDepsWithPath(depPrefix, http.Dir(targetDir))
+	if err != nil {
+		return "", fmt.Errorf("GenDepsWithPath failed: %v", err)
+	}
+	depsFile, err := ioutil.TempFile("", "camlistore_closure_test_runner")
+	if err != nil {
+		return "", fmt.Errorf("Could not create temp js deps file: %v", err)
+	}
+	err = ioutil.WriteFile(depsFile.Name(), b, 0644)
+	if err != nil {
+		return "", fmt.Errorf("Could not write js deps file: %v", err)
+	}
+	return depsFile.Name(), nil
+}
+
+// TestCwd runs all the tests in the current working directory.
+func TestCwd(t *testing.T) {
+	err := checkSystemRequirements()
+	if err != nil {
+		t.Logf("WARNING: JavaScript unit tests could not be run due to a missing system dependency: %v.\nIf you are doing something that might affect JavaScript, you might want to fix this.", err)
+		t.Log(err)
+		t.Skip()
+	}
+
+	path, err := os.Getwd()
+	if err != nil {
+		t.Fatalf("Could not determine current directory: %v.", err)
+	}
+
+	repoRoot, err := getRepoRoot(path)
+	if err != nil {
+		t.Fatalf("Could not find repository root: %v", err)
+	}
+	baseJS := filepath.Join(repoRoot, "third_party", "closure", "lib", "closure", "goog", "base.js")
+	bootstrap := filepath.Join(filepath.Dir(baseJS), "bootstrap", "nodejs.js")
+	depsFile, err := writeDeps(baseJS, path)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	c := exec.Command("mocha", "-r", bootstrap, "-r", depsFile, filepath.Join(path, "*test.js"))
+	b, err := c.CombinedOutput()
+	if err != nil {
+		t.Fatalf(string(b))
+	}
+}
diff --git a/server/camlistored/ui/blob_test.js b/server/camlistored/ui/blob_test.js
new file mode 100644
index 000000000..66295dd25
--- /dev/null
+++ b/server/camlistored/ui/blob_test.js
@@ -0,0 +1,104 @@
+/*
+Copyright 2014 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+goog.require('goog.crypt.Hash');
+goog.require('goog.crypt.Sha1');
+goog.require('goog.string');
+var assert = require('assert');
+var fs = require('fs');
+
+goog.require('camlistore.blob');
+
+
+var MockDOMBlob = function(buffer, start, end) {
+    this.buffer_ = buffer;
+    this.start_ = start;
+    this.size = end - start;
+};
+
+MockDOMBlob.fromSize = function(size, chr) {
+    var arr = new Uint8Array(size);
+    for (var i = 0; i < arr.length; i++) {
+        arr[i] = chr.charCodeAt(0);
+    }
+    return new MockDOMBlob(arr.buffer, 0, arr.length);
+};
+
+MockDOMBlob.prototype.slice = function(start, end) {
+    if (start < 0 || start >= this.size) {
+        throw new Error(goog.strings.subs("start '%s' out of range [0,%s)", start, this.size));
+    }
+    if (end < this.start_ || end > this.size) {
+        throw new Error(goog.string.subs("end '%s' out of range [0,%s)", end, this.size));
+    }
+    if (end < start) {
+        throw new Error(goog.string.subs("end '%s' is less than start '%s'", start, end));
+    }
+
+    return new MockDOMBlob(this.buffer_, this.start_ + start, this.start_ + end);
+};
+
+MockDOMBlob.prototype.getArrayBuffer = function() {
+    return new Uint8Array(this.buffer_, this.start_, this.size);
+};
+
+
+var MockFileReaderSync = function() {
+};
+
+MockFileReaderSync.prototype.readAsArrayBuffer = function(blob) {
+    return blob.getArrayBuffer();
+};
+
+
+describe('camlistore.blob', function() {
+  describe('#refFromHash', function() {
+    it('should calculate the right hash', function() {
+        var hash = new goog.crypt.Sha1();
+        assert.equal(camlistore.blob.refFromHash(hash), 'sha1-da39a3ee5e6b4b0d3255bfef95601890afd80709');
+
+        hash.reset();
+        hash.update('The quick brown fox jumps over the lazy dog');
+        assert.equal(camlistore.blob.refFromHash(hash), 'sha1-2fd4e1c67a2d28fced849ee1bb76e7391b93eb12');
+    });
+
+    it('should complain about wrong hash function', function() {
+        function FooHash() {};
+        goog.inherits(FooHash, goog.crypt.Hash);
+        assert.throws(camlistore.blob.refFromHash.bind(null, new FooHash()), /Unsupported hash function type/);
+    });
+  });
+
+  describe('#refFromString', function() {
+    it('should calculate the right hash', function() {
+        assert.equal(camlistore.blob.refFromString(''), 'sha1-da39a3ee5e6b4b0d3255bfef95601890afd80709');
+        assert.equal(camlistore.blob.refFromString('The quick brown fox jumps over the lazy dog'), 'sha1-2fd4e1c67a2d28fced849ee1bb76e7391b93eb12');
+    });
+  });
+
+  describe('#refFromDOMBlob', function() {
+    it('should calculate the right hash', function() {
+        blob = MockDOMBlob.fromSize(1000001, 'a');
+        goog.global.FileReaderSync = MockFileReaderSync;
+        try {
+            // Verified with openssl.
+            assert.equal(camlistore.blob.refFromDOMBlob(blob), 'sha1-432e7e01de7086c5246b6ac57f5f435b58f13752');
+        } finally {
+            delete goog.global.FileReaderSync;
+        }
+    });
+  });
+});
diff --git a/server/camlistored/ui/ui_test.go b/server/camlistored/ui/ui_test.go
new file mode 100644
index 000000000..2c721d5cd
--- /dev/null
+++ b/server/camlistored/ui/ui_test.go
@@ -0,0 +1,27 @@
+/*
+Copyright 2014 The Camlistore Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package ui
+
+import (
+	"testing"
+
+	"camlistore.org/pkg/misc/closure/jstest"
+)
+
+func TestJS(t *testing.T) {
+	jstest.TestCwd(t)
+}