Last Week in Pony - January 8, 2023

Sunday, January 08, 2023 | Posted in Last Week in Pony

The headline news of the week, if you are using Pony 0.52.3 to 0.52.5, you should update to 0.53.0 as soon as possible to address a runtime segfault.

Items of Note

Pony 0.53.0

Pony 0.53.0 was released last week. In contains an important fix for a runtime segfault. We advise updating as soon as you can.

Maybe Don’t Expect Instability

Last week, we wrote that we expected some instability due to the removal of an unsafe garbage collection optimization and the discovery of a bug that started happening because of the optimization removal.

At the time we started investigating the bug, it looked like it existed prior to the change, but was in a little used code path that might have never been stumbled upon. This intuition was arrived at because the bug wasn’t what we would have expected from the original change. However, that intuition was wrong.

The problem was in fact, an oversight in implementation of PR #4256. As Sean put it, “DUR!!!”. He subsequently fixed the issue in PR #4294 was was released as part of ponyc 0.53.0.

At this point, we are feeling pretty good about the optimization removal and Joe and Sean had a meeting on Friday to discuss some implementation details around iteratively adding back in the optimization where safe.

OpenSSL 3 Support is Here

We’ve updated ponylang/net_ssl, ponylang/crypto, and ponylang libraries that depend on net_ssl or crypto to support the OpenSSL 3 API.

Pony Development Sync

Audio from the January 3rd, 2023 sync is available.

A decent amount of time at sync was spent discussing a couple of older RFCs. Sean had started up conversation on them again. We decided to move forward with one and table another due to a lack of consensus.

There was some conversation around named arguments and our desire to see one or more RFCs proposing improvements. Both Sean and Joe encouraged folks to try coming up with proposals because they feel that improvements could be made, but they both also stated that they would be unlikely to support any given change and instead were looking for RFCs more to get the conversation going rather than one that would be accepted right away.

If you are interested in attending a Pony Development Sync, please do! We have it on Zoom specifically because Zoom is the friendliest platform that allows folks without an explicit invitation to join. Every week, a development sync reminder with full information about the sync is posted to the announce stream on the Ponylang Zulip. You can stay up-to-date with the sync schedule by subscribing to the sync calendar. We do our best to keep the calendar correctly updated.

Office Hours

We have an open Zoom meeting every Friday for the community to get together and well, do whatever they want. In theory, Sean T. Allen “owns” the meeting and will often set an agenda. Anyone is welcome to show up and participate. Got a Pony related problem you need help solving and prefer to do it synchronously? Give Office Hours a try.

What an office hours! 2 and half hours of discussion and teaching across a range of topics. The four attendees Adrian, Jairo, Red, and Sean decided that the summary would be…

“That was great! OMG we covered so much. You should have been here.”

Interested in giving attending Office Hours sometime? There’s a calendar you can subscribe to to stay up-to-date with the schedule. We do our best to keep the calendar up-to-date.


Highlighted Issues

Pony is a volunteer driven project. Nothing gets down without someone volunteering their time and helping to push things forward. Yes, there are folks who dedicate more time than others and a core team that dedicates time specifically for guiding Pony’s development. Everyone’s time is limited, so each week, we highlight a couple of issues that we hope will inspire someone to volunteer their time to help fix.

In addition to our highlighted issues, you can find more that we are looking for assistance on by visiting just about any repository in the ponylang org and looking for issues labeled with “help wanted”

If you are interested in working on either issue or any other issue from a Ponylang repository, you can get in touch on the issue in question or, even better, join us on the Ponylang Zulip to strike up a conversation.

This week’s issues as selected by Ryan A. Hagenson are:

Vague error messages when it is not safe to write

Currently, the error message produced when writing values only mentions the right-hand side. This can be really confusing when it is the left-hand side – and its reference capability – that is the cause of an error as the message diverts attention. Improving this error message would greatly improve debugging, especially for newer Pony developers who may not think to check the reference capabilities of both sides of an assignment.

ponyc #4290

Missing index check in deserialization

There is currently a missing index check in deserialization. Someone looking for a way to contribute to the compiler should give this issue a look!

ponyc #4297


Major changes in Pony go through a community driven process where members of the community can write up “requests for change” that detail what they think should be changed and why. RFCs can range from simple to complex. We welcome your participation.

We had a decent level of “RFC movement” this week. One new RFC was introduced; another was implemented, merged, and released; and two more were picked up again for some additional conversation leading to one starting to move toward a final comment period and another being put aside as lacking consensus.



Last Week In Pony is a weekly blog post to catch you up on the latest news for the Pony programming language. To learn more about Pony, check out our website, our Twitter account @ponylang, or our Zulip community.

Got something you think should be featured? There’s a GitHub issue for that! Add a comment to the open “Last Week in Pony” issue.

Interested in making a change, or keeping up with changes to Pony? Check out the RFC repo. Contributors welcome!


Sean T. Allen

Sean is a member of the Pony core team. His turn-ons include programming languages, distributed computing, Hiwatt amplifiers, and Fender Telecasters. His turn-offs include mayonnaise, stirring yogurt, and sloppy code. He is one of the authors of Storm Applied, and works at Microsoft Research.