For those just joining us: Conjecture is a radical simplification of property based testing, as popularised by QuickCheck. It emerged as a simplification of my work on Hypothesis, which is probably the second most advanced property-based testing system (after Quviq‘s QuickCheck for Erlang, and Hypothesis has a number of innovations over their work as well), and certainly the most advanced open source one.

Conjecture has some moderate usability advantages over Hypothesis, but its real advantage is ease of implementation in a new language: Hypothesis is almost impossible to port due to its extreme implementation complexity, while Conjecture is both easier to port and also can easily be written as bindings to a C library.

I’ve been holding off on progressing Conjecture out of its current research prototype state while I try to figure out the whole making open source work profitable thing, which is why it hasn’t seen any progress in a few months.

Unfortunately it turns out I’m really bad at not being allowed to work on software projects I’m interested in. What ends up happening is that I just write them in my head instead.

…which means that I accidentally figured out all the remaining questions for how to make Conjecture work. Then I cracked and couldn’t resist putting code to computer. As a result, I’ve put together a new prototype in Python and it has better data quality and shrinking than Hypothesis does. I now essentially consider the design of Conjecture a solved problem, and the open questions of whether it works answered with a resounding yes.

Moreover, it didn’t take me very long to implement at all. It took me so little time to implement that I’m reconsidering whether it’s actually even worth writing Conjecture as a C library. It’s almost easier just to port it.

So, uh, would you like one? Because I can write you one. My current estimate is that I can probably do a pretty solid implementation in a new language in not more than a month of work.

To be concrete about what I am offering:

- In almost any language of your choice, I am prepared to write something that is reasonably close to the Hypothesis core API (say, something akin to given, note + most of hypothesis.strategies). It will probably have some additional functionality, but the Hypothesis API is well proven in terms of its usefulness which makes it a good starting point.
- I do not anticipate that this will take more than a month, and a pretty usable prototype should emerge after about a week.
- I would charge you a day rate for my work. In exchange you would get a license to use but not redistribute all future released versions of Conjecture for that language without complying with the terms of the GPL (which it is otherwise released under).

Exact details are somewhat negotiable, but if you’re potentially interested, drop me a line.