coq VS Akka

The page summarizing the considered new names and their pros/cons is interesting: https://github.com/coq/coq/wiki/Alternative-names

Naming is hard...

Are those more important than, say:

- Proven with Coq, a formal proof management system: https://coq.inria.fr/

See in the real world: https://aws.amazon.com/security/provable-security/

And check out Computer-Aided Verification (CAV).

To be ruthlessly, uselessly pedantic - after all, we're mathematicians - there's reasonable definitions of "academic" where logical unsoundness is still academic if it never interfered with the reasoning behind any proofs of interest ;)

But: so long as we're accepting that unsoundness in your checker or its underlying theory are intrinsically deal breakers, there's definitely a long history of this, perhaps more somewhat more relevant than the HM example, since no proof checkers of note, AFAIK, have incorporated mutation into their type theory.

For one thing, the implementation can very easily have bugs. Coq itself certainly has had soundness bugs occasionally [0]. I'm sure Agda, Lean, Idris, etc. have too, but I've followed them less closely.

But even the underlying mathematics have been tricky. Girard's Paradox broke Martin-Löf's type theory, which is why in these dependently typed proof assistants you have to deal with the bizarre "Tower of Universes"; and Girard's Paradox is an analogue of Russell's Paradox which broke more naive set theories. And then Russell himself and his system of universal mathematics was very famously struck down by Gödel.

But we've definitely gotten it right this time...

[0] https://github.com/coq/coq/issues/4294

Dafny and Whiley are two examples with explicit verification support. Idris and other dependently typed languages should all be rich enough to express the required predicate but might not necessarily be able to accept a reasonable implementation as proof. Isabelle, Lean, Coq, and other theorem provers definitely can express the capability but aren't going to churn out much in the way of executable programs; they're more useful to guide an implementation in a more practical functional language but then the proof is separated from the implementation, and you could also use tools like TLA+.

https://dafny.org/

https://whiley.org/

https://www.idris-lang.org/

https://isabelle.in.tum.de/

https://leanprover.github.io/

https://coq.inria.fr/

http://lamport.azurewebsites.net/tla/tla.html

Still, there are many useful tools based on these ideas, used by programmers and mathematicians alike. What you describe sounds rather like Datalog (e.g. Soufflé Datalog), where you supply some rules and an initial fact, and the system repeatedly expands out the set of facts until nothing new can be derived. (This has to be finite, if you want to get anywhere.) In Prolog (e.g. SWI Prolog) you also supply a set of rules and facts, but instead of a fact as your starting point, you give a query containing some unknown variables, and the system tries to find an assignment of the variables that proves the query. And finally there is a rich array of theorem provers and proof assistants such as Agda, Coq, Lean, and Twelf, which can all be used to help check your reasoning or explore new ideas.

What ever happened to the effort [1] to rename Coq in order to make it less offensive? There were a number of excellent proposals [2] that seemed to die on the vine.

[1] https://github.com/coq/coq/wiki/Alternative-names

[2] https://github.com/coq/coq/wiki/Alternative-names#c%E1%B5%A3...

Information about the Coq proof assistant: https://coq.inria.fr/ , https://en.wikipedia.org/wiki/Coq

This type of thing can help you formally verify code.

So, if your proof is correct, and your description of the (language/CPU) is correct, you can prove the code does what you think it does.

Formal proof systems are still growing up, though, and they are still pretty hard to use. See Coq for an introduction: https://coq.inria.fr/

Most of the proof assistants out there: Lean, Coq, Dafny, Isabelle, F*, Idris 2, and Agda. And the main concepts are dependent types, Homotopy Type Theory AKA HoTT, and Category Theory. Warning: HoTT and Category Theory are really dense, you're going to really need to research them.

Kotlin also has a construct for asynchronous collections/streams. Kotlin's version of AsyncSequence is called a Flow. Just as Swift's AsyncSequence builds upon prior experience with RxSwift and Combine, Kotlin's Flow APIs build upon earlier stream/collection APIs in the JVM ecosystem: Java's RxJava, Java8 Streams, Project Reactor, and Scala's Akka.

First-class distributed and multicore computing. Swift has first-class “actors” and “distributed” methods. Unison, Erlang, and Elixir are built with distributed being one of the #1 concerns. Though first-class is not super common and I don't really expect it to be because usually libraries are enough (e.g. Scala has Akka and is used WIDELY for distributed); whereas something like linear types and typed effects, you can't emulate in a library.

Akka is a library that implements the actor model for JVM languages. Mainly in Scala, but you can use it in Java too, and maybe others. It doesn't feel as ergonomic as Elixir, but if Elixir is too "out there" for the decision makers in your case, this might be a friendlier alternative.

Kalix builds on the lessons we have learned from more than a decade of building Akka (leveraging the actor model) and our experience helping large (and small) enterprises move to the cloud and use it in the most time, cost, and resource-efficient way possible.

Note Akka, the Java & friends framework, is working with the actor model and have as main inspiration Erlang to mimic some features of the BEAM on top of the JVM.

Looking back at real dates, I started learning the language (Scala) back in 2008 because it was something new and trendy that interested me. I started spending some serious time with it in 2009 (helping out other newcomers and making small contributions to various projects), and then in 2010 became a core contributor to the Akka project (you can find me a little ways down this list: https://github.com/akka/akka/graphs/contributors). For the most part I worked on the features I wanted to, but worked on other things if a user asked nicely. Akka became very popular in the early 2010s, so all of a sudden I had highly sought after skills. Got hired by a London based company and moved myself and my family from Canada over here. But even today, that exposure I got 10 years ago still helps me to land new contracts.

In the open source world, Akka, the most popular actor system library in the JVM ecosystem, that’s heavily used in tonnes of open source projects, recently went from “free and open source” to “paid/proprietary and source available.” https://github.com/akka/akka/pull/31561

Same strategy - the pricing is insanely high (for a library), and the project is effectively dead now, but it’ll take some larger enterprises awhile to move away from.

Lightbend, the company owning Akka, recently shared a blog post signed by the CEO announcing a license change from Apache 2.0 to Business Source License 1.1, a proprietary license. You can already find it in this PR, merged a couple days ago.

Akka 2.6 is on the open source Apache license, that is unchanged (its not possible for Lightbend to change an existing license). Its only the new Akka 2.7 which has the BSL license, so as long as you don't upgrade you are fine. See https://github.com/akka/akka/pull/31561.