No, actually this is neither open source nor free software. The Open Source Definition requires the ability to redistribute changes: http://opensource.org/osd

The closest match would be Microsoft's Shared Source licenses.

(Life advice: don't be condescending without also being correct. Actually, you should probably just not be condescending.)

Love the double dipping. "GitHub can profit off your code, but you can't do anything with it and have no rights to it!"

In that case, keep your changes and improvements in your own branch, and don't submit a pull request for them. If you don't want to share it for "free," that's your call.

well, its not "your" code is it? GitHub have written it. If you don't want them to profit off your work, don't submit patches to Atom?

The whole point is they're trying to have it both ways. They want to benefit from other people's work freely (that's why they're accepting pull requests), but do not want to let others benefit from their work in the same way.

In production and development, open source as a development model promotes a) universal access via free license to a product's design or blueprint, and b) universal redistribution of that design or blueprint, including subsequent improvements to it by anyone. [1]

[1] http://en.wikipedia.org/wiki/Open_source

The exact definition of open source is up for debate.

Historically open source and free software have been synonymised in implementation, so it isn't surprising Wikipedia is using that definition.

However originally the idea was open source meant "you can look at and modify the code" while free software meant "you can redistribute the code".

I guess you can define terms however you wish but then you can't expect others to magically know your definition and "get it straight."

There is a commonly accepted definition of open source as published by OSI, and it is virtually identical to the definition of free software.