# Platforms and prerequisites ## Supported architectures The charm and its `app-image` resource on Charmhub are built for AMD64 only. Building from source works on AMD64 and ARM64: `app/rockcraft.yaml` and `app/charm/charmcraft.yaml` declare both, and [Improve the code](https://canonical.com/juju/docs/gopkg-charm/latest/contribute/improve-code/index.html.md#improve-code) covers the build. The observability charms are published for AMD64 only, so [How to integrate with COS Lite](https://canonical.com/juju/docs/gopkg-charm/latest/how-to/integrate-with-cos/index.html.md#integrate-with-cos) needs an AMD64 machine as well. ## Required tooling Deploying the charm requires the following snaps: - `juju` from `3/stable` - `microk8s` from `1.36-strict/stable` Checking a deployment from the command line uses `curl`, and using the service from a Go program, as the tutorial does in its last step, needs `go` from `latest/stable` and `git` from the Ubuntu archive. Building from source, covered by [Set up a development environment](https://canonical.com/juju/docs/gopkg-charm/latest/contribute/set-up-a-development-environment/index.html.md#set-up-a-development-environment) and [Improve the code](https://canonical.com/juju/docs/gopkg-charm/latest/contribute/improve-code/index.html.md#improve-code), adds: - `rockcraft` from `latest/stable` - `charmcraft` from `latest/stable` - `lxd` from its default channel, initialized with `lxd init --auto` - `tox` for the charm tests Both craft tools need experimental extensions enabled, which requires `ROCKCRAFT_ENABLE_EXPERIMENTAL_EXTENSIONS=true` and `CHARMCRAFT_ENABLE_EXPERIMENTAL_EXTENSIONS=true`. The documentation tests last verified the guides with Charmcraft 4.4.2, Rockcraft 1.20.0, Juju 3.6.28, MicroK8s 1.36.2, LXD 5.21.7, and Go 1.26.7 from the `go` snap. Newer releases from the same channels are expected to work; older releases are untested. The artifacts pin what they are built on: the charm uses the `ubuntu@24.04` base, the rock builds on `ubuntu@24.04` but ships with `base: bare`, the Go module requires Go 1.21.2 or later, and the charm depends on `ops` 3.8 and `paas-charm` 1.x. ## MicroK8s add-ons A deployment on MicroK8s needs these add-ons: - `dns`, which resolves names inside the cluster - `hostpath-storage`, which provides the volumes the Juju controller requests - `ingress`, which runs the ingress controller that publishes the service Building from source also needs `registry`, the local image registry on port 32000 that receives the rock.