Non of the code runs in chapter 11 (Can't set headers after they are sent)

Nobody has claimed this yet.

If you try running any code in chapter 11 you get the same error "Can't set headers after they are sent"

Express 3.0.0beta7
CoffeeScript version 1.3.3
Node v0.8.2

http.js:644
throw new Error('Can\'t set headers after they are sent.');
^
Error: Can't set headers after they are sent.
at ServerResponse.OutgoingMessage.setHeader (http.js:644:11)
at ServerResponse.res.setHeader (/Users/work/todo/node_modules/express/node_modules/connect/lib/patch.js:62:20)
at ServerResponse.res.header (/Users/work/todo/node_modules/express/lib/response.js:280:8)
at ServerResponse.res.json (/Users/work/todo/node_modules/express/lib/response.js:135:8)
at Create.global.Responder.Responder.complete (/Users/work/todo/src/controllers/responders/responder.js:27:25)
at Promise.__bind (/Users/work/todo/src/controllers/responders/responder.js:3:63)
at Promise.addBack (/Users/work/todo/node_modules/mongoose/lib/promise.js:120:8)
at Promise.EventEmitter.emit (events.js:88:17)
at Promise.emit (/Users/work/todo/node_modules/mongoose/lib/promise.js:59:38)
at Promise.complete (/Users/work/todo/node_modules/mongoose/lib/promise.js:70:20)

Start by running one of the chapter 11 examples with the listed CoffeeScript, Express, and Node versions, then trace the reported failure into src/controllers/responders/responder.js. Compare the other chapter 11 examples to determine whether they reach the same responder path; done means the chapter examples run without the reported headers error.

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