This is awesome! I have not really used nim for signal processing or data science work yet, but I think it would work very well with the right libraries, and this is one of the libraries that could make that happen.
Is this compatible with other libraries, such as arraymancer, etc? I think that one of the biggest strengths of the python numerical ecosystem is the good inter-operability of most plotting libraries with numpy. So if that is not already the case I would suggest making that your highest priority. Other than that, I didn't see mention of support for contour plots in the docs. It is surprising how often those come in handy in many scenarios so I'd like for you to add that if it is not available yet. Another thing I like to do is to combine line plots with histograms and/or kernel density plots on the X and Y axis (to get a quick idea of the distribution of the values, particularly in time series). It would be neat to support for that too. Finally, in signal processing work you are often working with complex samples. In that context it is often handy to plot the I and Q components vs time, placing 2 subplots on top of each other, and _[linking](https://forum.nim-lang.org/postActivity.xml#linking) the X (time) zoom/pan of the two subplots. It would be really nice if that were supported.