ferros VS hsluv

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.

Here's a potential solution to having consistent accessible color palettes in Koala: https://www.hsluv.org

If you want to take a step further, take a look into perceptually uniform color spaces, like HSL(uv) or LCh(uv).

Maxima enabled me to make my color space [HSLuv](https://www.hsluv.org/). I encoded CIELUV <-> RGB transformation functions into Maxima, ran `solve` and converted the output back into code. It's great to be able to commit [Maxima code](https://github.com/hsluv/hsluv/tree/master/math) into your repository and not leave the math as an "exercise to the reader".

If you want to make it more useful than a browser's built-in color picker, perhaps support other color spaces? Maybe HSLuv or CIE L*a*b*?

Chroma could be included, but as a minor criterion. When I look at color pickers that try to balance human perception against geometric simplicity like HSLuv and Okhsl, chroma is the property that gets distorted the most. Perceptual brightness and hue seem to be more important.

> Now, HSL isn't necessarily the best color mode to use in every situation; it tends to produce gradients that can be overly bright and vivid, because it doesn't take into account human perception.

Shout-out to to [HSLUV](https://www.hsluv.org/) which does exactly that.

I'm a little bit of a color freak. Allow me to leave some suggestions :)

- Picking from the 256 color pallete will likely give you colors with different brightness. This may hurt readability of darker colors on a dark background, and may make some color stand out unintentionally. Consider using something like HSLuv [1] to pick colors with the same lightness, then convert to the closest Xterm color [2].

- To make it obvious there is a gradient, I'd pick one lightness (assuming HSLuv) and one saturation (I usually stick to 100%), then pick a distance in hue for each step. For example if I expect to see a maximum of 7 steps on the screen at once, one way is to start at 0, then 30, then 60, etc. You may choose to go over 180, but keep in mind 360 will be the same as 0 so maybe stop at 240. Note how by picking adjacent colors from the table you are still picking a distance, but the distance is too small so it's hard to see.

- You may want to choose a different starting point than 0, and maybe different direction for the steps, depending on whether you want the colors to "mean" anything. For example red is commonly associated with warning, so you can arrange to have the top of the range aligned with red. Or arrange to avoid the red region if you don't want that association.

[1] https://www.hsluv.org/

Check out HSLuv as an alternative for UI design: https://www.hsluv.org/

HSLuv is a HSL alternative, which aims to maintain the perceived lightness of colors across the hue spektrum. It also includes a HPLuv variant, which additionally maintains saturation, at the cost of color coverage. Both are very useful for procedually generating or modifying colors. More Info: https://www.hsluv.org/comparison/