Chose your co-programmer.

From these stereotypes:

1:
Languages by experience: Bash, Python, Ruby, Perl, Haskell
Languages by love: Haskell, OCaml, Erlang, Scala, "Lisp"
Has written: Automated testing software, eStores, social network data mining software.
Favorite programs: Git, BSD, Vim, Sublime text, Twitter
Hates: Object oriented programming.
University grades: Completely average.

2:
Languages by experience: Java, C++, Smalltalk, Common Lisp, Forth
Language by love: Common Lisp, Forth, Smalltalk, Java
Has written: Equipment calibration, educational software, traffic control systems, signal processing and visualization
Favorite programs: Codewarrior, IntelliJ, Emacs, Zmacs, Macsyma, Mirai, Genera, Squeak, Mathematica, ACL2, Qemu, GNU Electric
Hates: UNIX
University grades: Very high, but two random fails.

3:
Languages by experience: C++, C#, x86, VB.NET, Delphi
Languages by love: Delphi, C#, x86, VB.NET, C++
Has written: Antivirus software, Serious Sam, natural language processing software
Favorite programs: Hiew, Visual studio, WinDbg, Borland Turbo Pascal, PIX, Windows 2000, FreeDOS.
Hates: Excessive use of libraries.
University grades: terrible.

Yourself and your co-programmer begin work. Your co-programmer has limited experience with JavaScript so you agree on him taking two weeks to experiment and get up to speed while you come up with the document structure and discuss with the back-end guy.

He reads "JavaScript the good parts" and seems to be making progress and you think "great I'll have my co-programmer just in time for the logic".

However, after this he learns of ClojureScript and decides that ClojureScript is the best way to do front-end web programming. He insists on using ClojureScript and, being curios, you give in.

After a week of going no where and spending your time with broken tools and debugging two languages simultaneously you say "Look it'll be easier if we just used plain JavaScript with JQuery". Your co-programmer argues and feels dejected but he eventually agrees.

You finally start making some progress and have most of the get queries going. Your co-programmer, upset with the "spaghetti code" and "inelegance" insists on using "Functional Reactive Programming" with "Elm". He also cites the "elegance" of its syntax and its similarity to Haskell. You adopt a different tactic this time and tell your colleague to see what he can do with it, while you work on what you already have.

You complete your logic while your colleague miserably tries to fit round pegs into square holes but always pesters you with every little accomplishment. He keeps reworking his more "elegant" rewrite of the logic, which begins to grow far more incomprehensible compared to your plain event driven JQuery, despite your colleague's insistence otherwise.

You spend the next two weeks writing the CSS and testing, and eventually both yourself and the customer are happy with it.

Your colleague did not help much, but at least you completed the project.