diff --git a/tools/jslint/check-all b/tools/jslint/check-all
new file mode 100755
index 0000000000..f008c4399e
--- /dev/null
+++ b/tools/jslint/check-all
@@ -0,0 +1,11 @@
+#!/bin/sh -e
+
+if which nodejs >/dev/null; then
+    # Name used by Debian etc.
+    NODE=nodejs
+else
+    # Name used by upstream
+    NODE=node
+fi
+
+$NODE "$0".js
diff --git a/tools/jslint/check-all.js b/tools/jslint/check-all.js
new file mode 100644
index 0000000000..96b1b8397e
--- /dev/null
+++ b/tools/jslint/check-all.js
@@ -0,0 +1,126 @@
+// Global variables, categorized by place of definition.
+var globals =
+    // Third-party libraries
+      ' $ jQuery Spinner Handlebars linkify'
+
+    // index.html
+    + ' initial_pointer email class_list people_list have_initial_messages'
+
+    // compose.js
+    + ' show_compose hide_compose toggle_compose compose_button'
+    + ' compose_class_name validate_message'
+    + ' status_classes'
+
+    // dom_access.js
+    + ' get_first_visible get_last_visible get_next_visible get_prev_visible'
+    + ' get_id get_zephyr_row'
+
+    // hotkey.js
+    + ' set_keydown_in_input'
+
+    // narrow.js
+    + ' narrowed show_all_messages'
+    + ' narrow_all_personals narrow_by_recipient narrow_instance'
+
+    // setup.js
+    + ' loading_spinner templates'
+
+    // subscribe.js
+    + ' fetch_subs sub_from_home'
+
+    // ui.js
+    + ' register_huddle_onclick register_onclick hide_email show_email'
+    + ' report_error clicking mouse_moved'
+    + ' update_autocomplete autocomplete_needs_update'
+
+    // zephyr.js
+    + ' zephyr_array zephyr_dict'
+    + ' status_classes clear_table add_to_table instance_list'
+    + ' keep_pointer_in_view prepare_huddle respond_to_zephyr'
+    + ' select_zephyr select_zephyr_by_id'
+    + ' scroll_to_selected select_and_show_by_id'
+    + ' selected_zephyr selected_zephyr_id'
+
+    ;
+
+
+var jslint_options = {
+    browser:  true,  // Assume browser environment
+    devel:    true,  // Allow console.log, etc.
+    vars:     true,  // Allow multiple 'var' per function
+    sloppy:   true,  // Don't require "use strict"
+    white:    true,  // Lenient whitespace rules
+    plusplus: true,  // Allow increment/decrement operators
+    regexp:   true,  // Allow . and [^...] in regular expressions
+    todo:     true,  // Allow "TODO" comments.
+
+    predef: globals.split(/\s+/)
+};
+
+
+// For each error.raw message, we can return 'true' to ignore
+// the error.
+var exceptions = {
+    "Expected '{a}' and instead saw '{b}'." : function (error) {
+        // We allow single-statement 'if' with no brace.
+        // This exception might be overly broad but oh well.
+        return (error.a === '{');
+    },
+
+    "Unexpected 'else' after 'return'." : function () {
+        return true;
+    }
+};
+
+
+var fs     = require('fs');
+var JSLINT = require(__dirname + '/jslint').JSLINT;
+
+var js_dir = __dirname + '/../../zephyr/static/js/';
+
+var exit_code = 0;
+
+fs.readdirSync(js_dir).forEach(function (filename) {
+    if (filename.slice('-3') !== '.js')
+        return;
+
+    var contents = fs.readFileSync(js_dir + filename, 'utf8');
+    var messages = [];
+
+    if (!JSLINT(contents, jslint_options)) {
+        JSLINT.errors.forEach(function (error) {
+            if (error === null) {
+                // JSLint stopping error
+                messages.push('          (JSLint giving up)');
+                return;
+            }
+
+            var exn = exceptions[error.raw];
+            if (exn && exn(error)) {
+                // Ignore this error.
+                return;
+            }
+
+            // NB: this will break on a 10,000 line file
+            var line = ('    ' + error.line).slice(-4);
+
+            messages.push('    ' + line + '  ' + error.reason);
+        });
+
+        if (messages.length > 0) {
+            exit_code = 1;
+
+            console.log(filename);
+
+            // Something very wacky happens if we do
+            // .forEach(console.log) directly.
+            messages.forEach(function (msg) {
+                console.log(msg);
+            });
+
+            console.log('');
+        }
+    }
+});
+
+process.exit(exit_code);