Use ect.js templates with hem by adding this to your slug.js for your spine.js project.

slug.js

var argv = process.argv.slice(2);
var fs = require('fs');
var path = require('path');
var hem  = new (require('hem'))();
var ect = require('ect');

// ect compiler
hem.compilers.ect = function(path) {
    var renderer, content, template;
    renderer = ect({});
    content = fs.readFileSync(path, 'utf8');
    template = renderer.compile(content);
    return "module.exports = (function(data){ return (function(){ return " + template.toString() + " }).call(data); })";
};


hem.exec(argv[0]);

Some relavent links:
baryshev/ect#17
https://github.com/eliseumds/ect