Ask HN: What are you working on? (October 2025)

Made a partially open source event platform for Pickleball and Badminton in Asia. Apart from managing event attendance, reminders, waitlist, level restrictions, and calendar syncing, there is also a pretty thorough Event Manager built in.

The event manager has a built-in ELO-style rating system designed for computer games and applies it to offline sports. You tap on the winning pair and it automatically calculates new ratings offline. It takes the attendees from the event automatically, and can manage taking turns evenly, placing players of similar level together and balancing matches. It can also do all of that while handling players who come in and out at random times, or matchmaking for fixed pairs.

So what problem does it solve? The event manager is a solution for anyone who organizes slightly larger groups of players. So instead of a a paddle queue or random-round robin tables, an event can be managed by level at a very granular level fully automatically. Players just go to the court they are assigned and they'll be put in a balanced competitive match automatically. At the end of the match the players just tap on the winning team. I think commercial facilities or clubs could also benefit from using this as it can do matchmaking for "open play" style events, but this is an open source side project and I have no intention of making any sales pitches.

https://www.pkuru.com - please check it out and if you are visiting Tokyo or Bangkok you can join the Pickleball events straight from the website.

I'm not actively planning for it, as I'm building this to fix a specific problem I have. However, it will be a static API and an SPA frontend, and both will be open source. The frontend should be fairly easy to reuse.

It will be on either of these accounts:

- https://github.com/nicbou/

- https://github.com/all-About-Berlin/

I'm working on a tool to auto-label emails in Gmail (first) based on what you've labeled in the past.

It pulls down up to 400 emails for each custom label and creates a custom model just for you, that will label new incoming email.

For emails that are likely, but not certain to be a particular label, I use a 'Proposed/{label}' approach which lets you just archive them in Gmail, and it will detect that they've been archived with the proposed label and move them to the correct label. (Essentially using the archive action as an acceptance criteria.) Similarly I use re-labeling by the user as a negative signal, and include that data as a counter-example.

It's working well for my own accounts, and the back-end is pretty legendary, but Google requires a hefty cost to audit security in order to turn it into a real product.

It always frustrated me that Google won't use their ML systems to label emails for me based on what I've done before. So I scratched that itch.

I'm using very straightforward BERT models right now, but I'm exploring using something a little more intelligent. I'm also exploring a multi-stage process, because a lot of emails can be categorized using much simpler techniques.

It's a great Machine Learning project, with a back-end that really runs spectacularly on Temporal and Kubernetes, and it's useful to me, so...wins all around.

I do wish I could make it a product, though.

Exactly my thoughts when I went through it.

I want to see the results of the test compared to the EU/US/Whoever recommendations. I want explanations of what the different chemicals are and preferably linked to peer reviewed studies explaining side effects.

Once even more tests are ran I want comparisons between product brands.

Overall still great but very much an engineer presentation to complex data. Not that its a bad thing, being transparent with data is important, but we aren't all experts.

I'm working on my (mostly) R7RS Scheme Interpreter. I've just finished call-with-current-continuation and exceptions which were rather difficult for me to grok. Currently working on improving the debugging experience before starting the monotonous work on implementing the ~400 required functions and documentation.

https://github.com/wmedrano/szl