7 ms·

so an abstration on top of docker?

by xlix 4y ago

pxc 4y ago
It uses the Docker CLI to build container images out of the Nix shells it creates, if you ask it to export one to a Docker image for you. Otherwise it just uses Nix locally, no virtualization. I wonder if it takes this approach because there's some issue with using Nixpkgs' dockerTools on macOS— those tools let you create Docker/OCI images without even having Docker installed.
- abathur 4y ago
  https://nix.dev/tutorials/building-and-running-docker-images#build-your-first-container https://nix.dev/tutorials/building-and-running-docker-images... asserts that you'd need a remote builder or cross-compiling. So it seems possible (unless maybe there are still enough cross-compile issues?)
  - pxc 4y ago
    Can cross builds hit the main binary caches or is that awaiting Hydra support for content-addressed derivations? Are there big caches for cross-compiled packages?
    - ParetoOptimal 4y ago
      I'm guessing awaiting based on how much rebuilding I had to do yesterday.
- honkler 4y ago
  docker is not virtualization either
  - pxc 4y ago
    1. Yes it is— there are many kinds of virtualization other than machine virtualization. Containers are a form of operating system virtualization. 2. Docker on non-Linux also requires machine virtualization; the `docker` CLI connects to a `dockerd` daemon running on a virtual machine. The question I posed earlier is motivated by understanding this and knowing that on macOS, the binaries that devbox runs on your local machine are completely different (of a different architecture, even) than the binaries that devbox will pack into a Docker image. Since it uses Nix to build them, it either needs to run Nix in a virtual Linux guest (which it does using the guest that Docker for Mac sets up) or have its Mac-bound Nix build Linux binaries. Using `docker buildx` obviates the need to set up devbox's own Linux VM to target as a remote builder, or, alternatively, cross compile the required Nix packages. But it comes at the cost of adding a dependency on Docker even though devbox doesn't use the Docker runtime for its shells
ParetoOptimal 4y ago
No, it just creates images compatible with docker.

so an abstration on top of docker?

by xlix 4y ago

so an abstration on top of docker?

pxc 4y ago

It uses the Docker CLI to build container images out of the Nix shells it creates, if you ask it to export one to a Docker image for you. Otherwise it just uses Nix locally, no virtualization. I wonder if it takes this approach because there's some issue with using Nixpkgs' dockerTools on macOS— those tools let you create Docker/OCI images without even having Docker installed.

abathur 4y ago
https://nix.dev/tutorials/building-and-running-docker-images#build-your-first-container https://nix.dev/tutorials/building-and-running-docker-images... asserts that you'd need a remote builder or cross-compiling. So it seems possible (unless maybe there are still enough cross-compile issues?)
- pxc 4y ago
  Can cross builds hit the main binary caches or is that awaiting Hydra support for content-addressed derivations? Are there big caches for cross-compiled packages?
  - ParetoOptimal 4y ago
    I'm guessing awaiting based on how much rebuilding I had to do yesterday.
honkler 4y ago
docker is not virtualization either
- pxc 4y ago
  1. Yes it is— there are many kinds of virtualization other than machine virtualization. Containers are a form of operating system virtualization. 2. Docker on non-Linux also requires machine virtualization; the `docker` CLI connects to a `dockerd` daemon running on a virtual machine. The question I posed earlier is motivated by understanding this and knowing that on macOS, the binaries that devbox runs on your local machine are completely different (of a different architecture, even) than the binaries that devbox will pack into a Docker image. Since it uses Nix to build them, it either needs to run Nix in a virtual Linux guest (which it does using the guest that Docker for Mac sets up) or have its Mac-bound Nix build Linux binaries. Using `docker buildx` obviates the need to set up devbox's own Linux VM to target as a remote builder, or, alternatively, cross compile the required Nix packages. But it comes at the cost of adding a dependency on Docker even though devbox doesn't use the Docker runtime for its shells

ParetoOptimal 4y ago

No, it just creates images compatible with docker.