87fc370541
Document the design and how to operate it: architecture, building (including toolchain-free/minimal builds), hardening guide, editions, observability, and the toolchain. README ties it together.
69 lines
3.0 KiB
Markdown
69 lines
3.0 KiB
Markdown
# Arcline OS — architecture
|
|
|
|
This is the foundation ("the wires") for Arcline OS: a hardened, Debian-derived
|
|
operating system for people who run infrastructure. The landing page describes
|
|
the product; this repository is how it gets built.
|
|
|
|
## Design goals
|
|
|
|
1. **Secure by default** — hardened kernel, default-deny firewall, AppArmor,
|
|
locked-down ssh. You opt *in* to exposure, never out.
|
|
2. **Zero telemetry** — no phone-home, no analytics, no cloud integration.
|
|
3. **btrfs-native** — snapshots and boot-to-snapshot rollback are built in.
|
|
4. **Production-ready from first boot** — observability pre-configured, tools
|
|
pre-installed, everything documented.
|
|
5. **Auditable** — every script and config is plain text in this repo.
|
|
|
|
## How a build flows
|
|
|
|
```mermaid
|
|
flowchart LR
|
|
A[editions/* metadata] --> B[debootstrap<br/>Debian bookworm]
|
|
B --> C[install edition<br/>packages.list]
|
|
C --> D[apply overlays<br/>base + edition]
|
|
D --> E[configure-system.sh<br/>in chroot]
|
|
E --> F[rootfs .tar.xz]
|
|
F --> G[grub-mkrescue + squashfs<br/>→ live ISO]
|
|
E -.toolchain .debs.-> C
|
|
```
|
|
|
|
Pipeline stages live in `scripts/`:
|
|
|
|
| Stage | Script | What it does |
|
|
|-------|--------|--------------|
|
|
| bootstrap | `build-rootfs.sh` | debootstrap minbase, apt sources, package install |
|
|
| overlay | `apply-overlays.sh` | copies `overlays/base` + `overlays/<edition>` into the rootfs |
|
|
| configure | `configure-system.sh` | runs *in the chroot*: hostname, locale, kernel cmdline, services, live-boot, toolchain |
|
|
| package | `build-iso.sh` | kernel + initramfs + squashfs → hybrid BIOS/UEFI ISO |
|
|
| orchestrate | `build-edition.sh` / `Makefile` | wire the above to `make iso-<edition>` |
|
|
|
|
## The four source trees
|
|
|
|
| Path | Role |
|
|
|------|------|
|
|
| `editions/` | per-edition **manifests**: package lists, kernel cmdline, fstab, metadata |
|
|
| `overlays/` | **files that land in the image**, organised as layered rootfs trees |
|
|
| `scripts/` | the **build pipeline** (all plain bash, readable top to bottom) |
|
|
| `btrfs/`, `toolchain/`, `observability/`, `tests/`, `ci/` | supporting subsystems |
|
|
|
|
There is no hidden magic: the Makefile is a thin wrapper, `versions.mk` /
|
|
`scripts/common.sh` hold the single source of truth for versions and paths.
|
|
|
|
## Zero telemetry, enforced
|
|
|
|
- No distro telemetry packages are installed (`ubuntu-report`,
|
|
`popularity-contest`, snapd are never in a package list).
|
|
- apt automatic-update timers are **masked** in every edition's metadata.
|
|
- The firewall's output chain never initiates calls on its own.
|
|
- cloud-init is pointed only at the configured cloud datasource.
|
|
- The smoke tests (`tests/smoke/verify-rootfs.sh`) fail the build if telemetry
|
|
artifacts are found.
|
|
|
|
## Follow-up work (explicitly out of scope for "the wires")
|
|
|
|
- Partitioning/installer that runs `btrfs/init.sh` on a target disk.
|
|
- Cloud images (qcow2/raw) for the `cloud` edition — the ISO path is wired,
|
|
a disk-image path is the next step.
|
|
- Grafana/Loki packaged as `.deb`s rather than fetched from upstream.
|
|
- A signed (secure-boot) kernel for official releases.
|