There's quite a few opportunities I see from looking around in EA. I am doing direct technical work for EA right now.
EA CoLabs itself can be framed as a technical problem. It's the problem of optimally matching different skillsets to different projects to maximise utility. You could definitely tackle it from a fun technical perspective (say, using the Hungarian Algorithm for matching, and using the Australian Skills Classification to describe skills). These however are just my ideas. I may be currently too busy with other things to properly investigate whether this is feasible.
Certificates of Impact and EA Economies
There are a lot of interesting ideas in creating economies around EA. For instance, having people sell products where all proceeds go to charity. I have a friend who wishes to look into using technologies such as blockchain to track coins that can be used to purchase good where the profits end up to Effective Charities.
Improving Infrastructure around Cost Effectiveness Analysis
This is what I'm currently doing as direct work. Cost Effectiveness Analysis are not really done to a very high quality in EA spaces as yet, and it would be nice to see more analysis so that we can make more informed decisions. I see this as a major tooling opportunity, as the state of the art in this area uses excel and a lot of time. This may include improving on technologies like Guesstimate, or building entirely new technologies.
Improving Infrastructure around epistemics and forecasting
The next area I would highlight is that there needs to be better evaluations of things like Cost Effectiveness Analysis, or really any other important calculations or predictions. These evaluations often aren't really done, and I would love to see proper evaluations say for parameters in GiveWell's Cost Effectiveness Analysis.
If you are interested in any of these. Please reply/get in contact.