Field such as Web/Datascience are already filled by Python/Ruby and Java. Any ideas?
I like the projects in here: https://github.com/Araq/Nim/wiki/GSoC-2015-Ideas
But I don't think there's anything perfectly fitting for what you're looking for in there.
Don't blame me for stuff being hard to do :)
how about doing an opensource clone of something closed sourced,system software, but big enough that maintainability and performance matters?
zsync is already opensourced right? as it is already in C , rewriting it will make no difference. bup is more interesting because bup clone in nim can speed it up , and as bup is in python we can even copy some code lol, nim is most pythonic of non-python variants.
I think it's need to be something new or something that's works with leading trends like IoT, mobile, big data, devops (like Docker). I came across http://matrix.org and this thread today and I think that this fits perfectly :)
Matrix claims to be Open Standard with Open Source Implementations done mostly in Python. There's home server reference implementation https://github.com/matrix-org/synapse that can be rewritten in Nim to show its strength over Python and Go https://github.com/KoFish/pallium. I dunno if I can find time to work on it but it could be something interesting.
Do we have websocket support in Nim?
There seems to be a library in progress: https://github.com/onionhammer/onion-nimrod/tree/master/websockets
Alternatively you can use websocketd of course: https://github.com/joewalnes/websocketd