Dear jhk753,

Thank you for your contribution to the hitbtc community!

Here're some comments on your code:
1. You can get duplicated nonce by using your nonce generation routine. In fact you are using current UNIX timestamp (in seconds) and you library won't make more then 1 call per second.
It's much better to get the millisecond timestamp on the application start/class instantiation and then increment the counter each call.
2. Better to have a version of the cancel_order method that doesn't call active_orders. You make 2 API calls for one operation.
Also consider storing placed orders in the application memory.

Don't you mind publishing a link to your github repo in the Community libraries section of hitbtc API documentation?

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