[Ethereum] Truffle does not add “networks” to build/contracts/contract.json after migration

You are on the old documentation (for truffle v2.x). The new documentation for Truffle v.3.x is here

The migration process between the versions is explained here:

Build Pipeline: No more builder, by default In Truffle 1.0 and 2.0, things were heavily geared toward building web applications, and so Truffle shipped with a default build pipeline that could get your dapp up and running quickly. This build pipeline was magical: It did everything for you, and you didn't have to lift a finger. This was good for some use cases, but it became evidently clear that in any other use case the pipeline was very brittle.

Over the last year, Ethereum-enabled applications have only been growing. What started out as solely a platform for web application, now dapps can be written in native languages and run as standalone applications on mobile and the desktop. Truffle has always intended to support these use cases, and so that's why we removed the default build pipeline from Truffle. You can still write your own custom build pipeline if you'd like to tightly integrate it with Truffle, but by default Truffle will focus on continuing to be the best tool for smart contracts around. We'll let the better build pipelines – like webpack, browserify, Grunt, Metalsmith – do the job of, well, building.

Now, just because the build pipeline has been removed by default doesn't mean you don't have options. At Truffle, we care about your developer experience and so would never leave you hanging. In general there are two options for you to choose from, but for the latter option what you'll do is heavily dependent on which build tool (i.e., webpack) you choose to use. Let's go over the options below.

All of that means that the Truffle config file can't contain a build setup anymore. Just remove the build part:

truffle.js

module.exports = {
  networks: {
    development: {
      host: "localhost",
      port: 8545,
      network_id: "*" // Match any network id
    }
  }
};

I actually found out the reason it wasn't migrating was that Parity has a few super well hidden processes that didnt show up when I did ps -a ; After finding that parity process and killing it, it worked like a charm.