abstreet VS unsafe-code-guidelines

Super awesome! I like how you just color roads to show time. When you calculate polygons to try and cover the whole area in some 5-10 minute bucket, you can wind up with all sorts of odd holes far away from roads. Keep it simple.

https://github.com/a-b-street/abstreet/pull/1075

A|B Street does some of that, but it is not a game: https://github.com/a-b-street/abstreet

You can build it out in a cool simulator and show it off.

The tool you want exists, but you'll need to actually build the city in it. It's really an incredible program!

Active Travel England | Software Developers and Data Engineer | Full or Part Time | https://www.gov.uk/government/organisations/active-travel-en...

Active Travel England will be developing tools to support evidence-based investment and policies to support sustainable transport. We're hiring 3 roles at present (there will be more jobs in January): https://www.civilservicejobs.service.gov.uk/csr/index.cgi?SI...

We are already working with the transport simulation and scenario development tool A/B Street and the Low Traffic Neighbourhood design tool: https://a-b-street.github.io/docs/ and plan to create new web applications to transform active travel infrastructure design, monitoring and evaluation.

An exciting thing about these jobs from a software engineering perspective is that you will be starting with a relatively blank slate. In the UK we already have tools like https://bikedata.cyclestreets.net and https://www.pct.bike/ but need to go further than this. Long term, the 7 strong Data and Digital team that you will be part of will develop a comprehensive map based design support tool to provide data of the type in BikeData (and more datasets), drawing tools, and automated assessment of proposed interventions.

These opportunities will enable you to shape the future of tools for active travel investment and policy in England and, because the software develop as part of these roles will be open source, beyond.

These high profile jobs will have a large impact, see here for context: https://twitter.com/Chris_Boardman/status/159648662743800217...

I don't know the topic well enough to be sure, but isn't this what you're looking for: https://github.com/a-b-street/abstreet

https://github.com/a-b-street/abstreet - project to plan, simulate, and communicate visions for making cities friendlier to people walking, biking, and taking public transit.

Useful context on the Rust side is this issue [1]. It sounds like some of the author's concerns are addressed already.

[1]: https://github.com/rust-lang/unsafe-code-guidelines/issues/4...

Is this captured by one of the known soundness conflicts? If not then should consider adding it to the list.

There are some competing proposals for different memory models. Stacked borrows is the current proposal, but there are more work in the approproate WG.

Thank you /u/RalfJung for bringing formal methods to Rust, both through models like Stacked Borrows, by developing miri, and by working on unsafe-code-guidelines which aims to specify exactly what is and isn't allowed in unsafe code (surprisingly, it's an open question as 2023!)

You could imagine some way to make this safe for example automatically convert &'short &'long mut T to &'short &'short T, but it's non-trivial to prove they are safe at all, not to mention ensuring this is correctly implemented in the compiler. If you're interested there's also a discussion on whether the opposite (& & T to & &mut T) is sound here.

Agreed! MIRI is so good, it still feels like magic to me. It also comforts me that the Rust team takes improving unsafe semantics seriously, with the past Unsafe Code Guidelines WG and today's operational semantics team (t-opsem).

I think there are some aspects of this rule that are still undecided. See for example:

- https://github.com/rust-lang/unsafe-code-guidelines/issues/8...

- https://github.com/rust-lang/miri/issues/2732

C is much better specified than unsafe Rust. Some things are just not worked out yet in Rust. This may sometimes even bite very experienced devs, such as this issue with Box's aliasing semantics, which tripped up the author of left-right.