Pre-compile your client-side underscore templates to individual AMD modules using Node.js.

compile_underscore_templates.js

/*

Underscore Template AMD Compiler
Ryan Blunden

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.
*/

var fs = require('fs');
var path = require('path');
var _ = require('underscore');

var TEMPLATE_EXT_REGEX = /\.(html|tmpl)$/;
var TEMPLATE_BASE_PATH = __dirname + '/PATH/TO/TEMPLATES/';

/**
 * Compile an underscore template source to an AMD module
 *
 * @param template {String}
 * @returns {String}
 */
function compileTemplateSourceToAMD(template) {
  return 'define(function() { return ' + _.template(template).source.replace(/[\r\n\t]+/gm, '') + ' });';
}

_.each(fs.readdirSync(TEMPLATE_BASE_PATH), function (file) {
  if (!TEMPLATE_EXT_REGEX.test(file)) {
    return;
  }

  var inputFile = TEMPLATE_BASE_PATH + path.sep + file;
  var outputFile = TEMPLATE_BASE_PATH + path.sep + file.split('.').slice(0, -1) + '.js';

  fs.writeFileSync(outputFile, compileTemplateSourceToAMD(fs.readFileSync(inputFile).toString('utf-8')));
});