composeMiddleware.es6

// const composed = composeMiddleware(fn1, fn2, fn3);
const composeMiddleware = (head, ...tail) => (req, res, next) =>
    head instanceof Function ?
        head(req, res, () => composeMiddleware(...tail)(req, res, next)) :
        next();
        
// var composed5 = composeMiddlewareES5([fn1, fn2, fn3]);
var composeMiddlewareES5 = funcs => (req, res, next) =>
    funcs[0] instanceof Function ?
        funcs[0](req, res, () => composeMiddlewareES5(funcs.slice(1))(req, res, next)) :
        next();