blumeops/docs/explanation/why-gitops.md
Erich Blume b197bd5f58 Adopt Dagger CI for docs build (Phase 2) (#157)
## Summary

Migrates the docs build pipeline to Dagger (Phase 2 of the Dagger CI adoption plan).

- **Backfill `date-modified` frontmatter** on all 80 docs — Dagger's `--src=.` excludes `.git`, so Quartz can't use git history for page dates. Frontmatter dates work with or without git.
- **New `docs-check-frontmatter` mise task + pre-commit hook** — validates all docs have `title`, `tags`, and `date-modified`
- **New Dagger functions** — `build_changelog` (towncrier in Python container) and `build_docs` (chains changelog → Quartz build in Node container, returns tarball)
- **Simplified CI workflow** — the ~44-line inline Quartz build (clone, npm ci, build, tar, cleanup) is replaced by `dagger call build-docs`. Changelog step remains local on the runner since towncrier needs to modify the host working tree for the git commit.

### Design decisions

- **Towncrier runs twice in CI**: once inside Dagger (for the docs tarball) and once on the runner (for the git commit). This is intentional — Dagger's directory export is additive and can't delete the consumed changelog fragments from the host.
- **Artifact hosting stays on Forgejo Releases** (not migrated to Forgejo Packages as the plan doc originally suggested). That migration can happen independently.
- **`date-modified` frontmatter** preserved even though `build_changelog` installs git — the git there is only for towncrier's `git add` call, not for history. The local iteration story (`dagger call build-docs --src=. --version=dev` with uncommitted changes) depends on frontmatter dates.

### Local iteration

```bash
dagger call build-docs --src=. --version=dev export --path=./docs-dev.tar.gz
tar tf docs-dev.tar.gz | head -20
```

## Deployment and Testing

- [x] `dagger call build-docs --src=. --version=dev` produces valid 1.1MB tarball (149 HTML pages)
- [x] Pre-commit hooks pass (including new `docs-check-frontmatter`)
- [ ] Full `workflow_dispatch` run after merge

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Reviewed-on: https://forge.ops.eblu.me/eblume/blumeops/pulls/157
2026-02-11 16:33:16 -08:00

2.7 KiB

title date-modified tags
Why GitOps 2026-02-07
explanation
philosophy

Why GitOps?

Note: This article was drafted by AI and reviewed by Erich. I plan to rewrite all explanatory content in my own words - these serve as placeholders to establish the documentation structure.

BlumeOps uses GitOps principles for managing personal infrastructure. This might seem like overkill for a homelab, but there are good reasons.

The Problem with Manual Infrastructure

Traditional server management involves SSHing into machines and running commands. This works, but creates problems:

  • Drift: The actual state diverges from what you think it is
  • Amnesia: You forget what you changed and why
  • Fragility: One bad command can break things with no easy rollback
  • Bus factor: Only you know how it works (even AI assistants struggle without context)

Git as the Source of Truth

GitOps inverts the model: instead of pushing changes to servers, you commit desired state to Git, and automation pulls it into reality.

Benefits:

  • Every change is tracked with commit history
  • Pull requests enable review before deployment
  • Rollback is just git revert
  • The repo is the documentation

Why This Matters for a Homelab

A personal homelab isn't a production environment, but it shares the same challenges:

  1. Memory is unreliable - Six months from now, you won't remember why you configured Caddy that way
  2. Experimentation is constant - You try things, break things, want to undo things
  3. AI assistance needs context - Claude can help much more effectively when it can read your infrastructure as code

The BlumeOps Approach

BlumeOps uses layered GitOps:

Layer Tool What it manages
Tailnet [[tailscale Pulumi]]
Host config [[roles Ansible]]
Kubernetes [[argocd ArgoCD]]

Each layer has its own reconciliation loop:

  • Pulumi applies on mise run tailnet-up
  • Ansible applies on mise run provision-indri
  • ArgoCD watches Git and syncs manually or automatically

Trade-offs

GitOps isn't free:

  • Learning curve - You need to understand Ansible, ArgoCD, Pulumi
  • Indirection - Can't just apt install something; need to add it to config
  • Complexity - More moving parts than a simple server

But for BlumeOps, the trade-off is worth it. The infrastructure is complex enough that managing it imperatively would be error-prone, and the GitOps approach enables effective AI-assisted operations.