ferros VS git-subrepo

My company, https://www.auxon.io. We created https://github.com/auxoncorp/ferros originally to enable a customer project early in the company's life cycle.

Some time later we had another customer interested in using it and having us add some features to it (e.g. some device drivers and a persistence layer utilizing https://docs.rs/tickv/latest/tickv/). It was becoming a massive pain in the neck to work out source code sharing agreements with them, so we decided to just open source it.

There are quite a number of things that we would do differently if we had to build it again, and at some point will likely do that work to revise it. The biggest one of those is root task synthesis. The other is to build and bring in facilities for running tasks that are compiled to WASM.

When we add WASM support to https://github.com/auxoncorp/ferros it'll sorta be like what you're angling at there in your description.

We've built things on seL4 (https://github.com/auxoncorp/ferros). We like to joke that it's the most perfect piece of nearly featureless software ever made.

There's... A LOT... of work to do before seL4 is going to be anywhere near usability parity with something like Linux, unfortunately.

Rather than make a general purpose OS, we decided to use it more like a unikernel or "library OS" where you're trying to make a well defined kind of "appliance" image to deploy to specific hardware rather than try to fake being a POSIX-y shaped OS.

For what it's worth, here's FerrOS's repo as well as the underlying selfe repo

That's basically what we did with https://github.com/auxoncorp/ferros, Bundle Rust programs together as tasks to run atop the formally verified seL4 microkernel.

We also built a Rust framework called FerrOS (https://github.com/auxoncorp/ferros) atop the formally-verified seL4 microkernel.

It has a similar set of usage idioms to Hubris it looks like in terms of trying to setup as much as possible ahead of time to assemble what's kind of an application specific operating system where everything your use case needs is assembled at build-time as a bunch of communicating tasks running on seL4.

We recently added a concise little persistence interface that pulls in TicKV (https://docs.tockos.org/tickv/index.html) from the Tock project you referenced above, and some provisions are being added for some more dynamic task handling based on some asks from an automotive OEM.

We built a thing to enable combining Rust applications together to be hosted on the seL4 microkernel. The developer experience is more akin to that of something like an RTOS where the OS and your applications are built and deployed together. The whole premise of it is decidedly non-POSIX-like. The current point is for assembling software for use-case-specific/appliance computing, not general purpose computing. (https://github.com/auxoncorp/ferros)

We're looking both for contributors and also actively hiring for a couple engineering positions for the above and for or mainline product.

I tried and failed to bring unikernels to my former work when I was at Visa. Specifically, LING.

At my current company, Auxon, we recently open sourced[1] some work we did a couple years back which is more or less an attempt at the basic foundations for blending the seL4 microkernel with fairly normal no_std Rust application development and assembling them all together to make a purpose built OS/application to deploy directly to hardware or within a VM. We have some work to do to keep building it up as a foundation for broader use, but we're looking into partnering with the seL4 Foundation (now under the Linux Foundation) to iterate on it further with some of our other mutual partners. The developer experience is much closer to that of developing for an RTOS than it is like typical general purpose computing development.

I'm of course biased, but I think there's a lot of room to innovate in the space of use case specific software stacks where the domain and constraints are well understood and too many degrees of freedom are actually a hindrance and a liability, not an advantage.

[1] https://github.com/auxoncorp/ferros

On top of that is ferros (no relation to to ferrous-systems), a higher-level userland of unreasonably strong types for compile-time resource tracking. No more discovering you need more memory, or capability slots or IPC rights at runtime. These types help you fit the right seL4 screw to the right seL4 screwdriver.

git-subrepo - complicated and difficult to understand

I find the following approach more consistent to manage components: https://github.com/ingydotnet/git-subrepo . And native package management systems, like npm in JavaScript universe, superior to either of the above. But the choice of a particular method depends on problems we need to solve. In terms of one-time codebase aggregation method they are all equally fine.

I much prefer https://github.com/ingydotnet/git-subrepo

Where I work we just package everything (nugets, python packages, npm) on our Artifactory. Contracts dependencies (DLLs, protobufs) are also distributed as packages. We made it easy to fetch and test the source and allow developers to develop, debug and test those dependencies with their own project if needed.

Every time we try to assemble repositories in macro-repos we always end up regretting it. Multiple dedicated repositories allow autonomy for teams and enforce modularity and coding as a library. Monorepos have a tendency of becoming huge merge trains easily and often derailed and with lots of fear of being blamed on stepping on someone else's toes.

We update often all our projects knowing full well that not doing so is just borrowing development time at high interest rate.

As a side-note when we do have to do an assembly of different code base, we use git-subrepo: https://github.com/ingydotnet/git-subrepo which provide the best of both submodules and subtree.

v2: I use git subrepo or a similar tool, to get the upstream yaml into my repo.

I found git-subrepo: https://github.com/ingydotnet/git-subrepo

You might also check out git subrepo.

Besides these git x-modules, there are historically three contenders:

git submodules: https://git-scm.com/book/en/v2/Git-Tools-Submodules

git subtrees: https://www.atlassian.com/git/tutorials/git-subtree

git subrepos: https://github.com/ingydotnet/git-subrepo

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git subrepos work simply by copying your dependency to a subdirectory and committing the changes using one large commit that retains metadata about the update to the subrepo. For that reason, git subrepos aren't symlinks. You don't need to git clone --recursive like with git submodules, and you don't need cross-repo authentication. Updating a subrepo means performing another commit.

Even though git subrepos are the most poorly maintained, the design is simpler.

I wish someone would fork and take over maintenance.

git subrepos are the best.