Show HN: Hacker News job trends

When using multiple keyword with the + and - signs, it graphs the sum of all posts requiring one technology in addition to all posts requiring the other technology.

It'd be great if there was a way to graph sum of all posts that require both (or more) technologies. I have tried with spaces and comas etc... (eg: 'rust, python') but it doesn't work well as you have to guess exact matches (so 'rust, python' is a different result than 'python, rust').

You can also end up with results like some months having a negative number of posts. I think the intuitive meaning of any arithmetic operators here would be set operations.