# .goosehints for dumpnet-argo

This is a personal single-node Talos/Kubernetes cluster on AWS EC2, managed via
ArgoCD GitOps, migrating services off a legacy NixOS box (dumpnet.chat /
git.keane.sh). Below are conventions and hard-won lessons — follow them
before improvising a new pattern.

## Core architecture

- Single EC2 node (t3.medium), Talos Linux, one EIP, one cluster — this will
  **never** be multi-node. Don't suggest multi-node solutions (NLB, EFS for
  RWX, etc.) as the default; hostPath/local-disk patterns are correct here.
- Terraform (`terraform/`) owns all AWS infra: EC2, EIP, subnet, security
  group, Talos bootstrap, Route53, S3, IAM, Secrets Manager, SES.
- ArgoCD App-of-Apps owns all Kubernetes-side resources. Root app is
  `apps/apps.yaml`, which points at the `apps/` directory itself (self-managing,
  only needs one manual `kubectl apply` ever, via `make bootstrap`).
- Groups under `apps/`: `cluster.yaml` (platform infra), `data.yaml` (shared
  stateful stuff like Postgres), `services.yaml` (user-facing apps), `mcp.yaml`
  (MCP servers). Manifests live in matching `manifests/<group>/` dirs. Add new
  groups here rather than growing one flat directory.
- One global `values.yaml` at repo root holds `clusterName`, `domain`,
  `repoURL`, `certEmail`, `awsRegion`, `registry.*`. Charts read it via the
  multi-source `$values/values.yaml` pattern. `repoURL` inside ArgoCD
  `Application` specs themselves can NOT be templated (Helm doesn't touch
  those fields) — document this when it matters, don't try to fix it.

## Secrets

- **Exactly one** AWS Secrets Manager secret: `dumpnet` (nested JSON by
  service, e.g. `cluster`, `postgres`, `kan`, `forgejo`, `ses`,
  `tailscale`, `mcp_auth_proxy`). Never create a second Secrets Manager
  secret — Secrets Manager billing is per-secret and that was an explicit
  decision to avoid.
- External Secrets Operator (ESO) is the only way secrets get into the
  cluster. `ClusterSecretStore` auths via the EC2 instance IAM role — no
  static credentials anywhere.
- Sensitive local files (`controlplane.yaml`, `worker.yaml`, `talosconfig`,
  `terraform.tfstate`) are gitignored entirely — never SOPS-encrypted in-repo.
  Decrypt-to-`/tmp` was rejected in favor of "never committed at all."
  `terraform.tfvars` is intentionally NOT gitignored (values aren't
  sensitive) — don't re-add it to `.gitignore`.
- When adding a new service's secrets: add the key(s) under the service's
  namespace in the `dumpnet` JSON blob (via `aws secretsmanager
  get-secret-value` → merge in Python → `put-secret-value`), then add an
  `ExternalSecret` template in that chart's `templates/` dir referencing
  `property: <service>.<key>`.

## ArgoCD / Helm patterns (learned the hard way)

- **Use charts as-is.** Don't split an app into multiple ArgoCD Applications
  just because another unrelated chart happens to be split that way (this
  was explicitly called out as "cargo culting" — cert-manager's
  ClusterIssuer split is justified due to CRD ordering; ESO's original split
  was not and got merged back into one app).
- Extra resources (ClusterSecretStore, Issuers, Namespaces, ExternalSecrets)
  belong in that chart's own `templates/` directory, not a second
  Application, unless there's a *proven* cross-app ordering problem.
- Any namespace that needs `hostNetwork`, `hostPath`, or other privileged
  pod behavior (ingress-nginx, fluent-bit, tailscale, mcp-auth-proxy) needs a
  `Namespace` manifest in that chart's `templates/` with:
  ```yaml
  metadata:
    labels:
      pod-security.kubernetes.io/enforce: privileged
      pod-security.kubernetes.io/audit: privileged
      pod-security.kubernetes.io/warn: privileged
  ```
  Do **not** create these namespaces via Terraform `kubernetes_namespace` —
  that was tried and reverted; it causes import/ordering pain on rebuilds.
  ArgoCD-managed namespace manifests are the correct pattern.
- ESO `ExternalSecret` `.target.template` uses its own Go-template syntax
  that Helm will try to consume if you're not careful. To keep a value
  literal for ESO to interpolate at runtime while still letting Helm
  interpolate `.Values.*`, use the `{{ "{{" }}` / backtick escaping pattern
  already present in `charts/*/templates/*.yaml` — copy that pattern rather
  than reinventing it.
- Watch out for fields ESO/operators add as defaults after creation
  (`mergePolicy`, `engineVersion`, etc.) causing perpetual ArgoCD
  OutOfSync — either match them explicitly in the manifest or use
  `ignoreDifferences` in the Application spec.

## Storage

- Single shared hostPath-backed PV (`appdata`, ReadWriteMany, `Retain` reclaim
  policy) at `/var/local/appdata` on the node. Services claim subpaths via
  their own PVCs bound to that PV — this is the deliberate "Unraid appdata"
  equivalent for a single-node cluster. Don't provision per-service EBS
  volumes or suggest EFS/CSI drivers unless the user explicitly wants to
  outgrow single-node.
- PV `capacity` on hostPath volumes is a label, not an enforced quota — don't
  be alarmed if it's set higher than the actual disk size, but don't blow
  past real disk space either.

## Networking / TLS

- ingress-nginx runs as a DaemonSet in `hostNetwork` mode (binds 80/443
  directly on the node) — no LoadBalancer/NLB. This was a deliberate
  cost-saving choice for single-node.
- cert-manager + Let's Encrypt (`letsencrypt-prod` ClusterIssuer, HTTP01 via
  ingress-nginx) for all public hostnames. A separate `selfsigned` Issuer
  handles internal webhook certs (e.g. ESO) — never try to get Let's Encrypt
  certs for internal `*.svc.cluster.local` names, it will always fail with
  "domain needs a public suffix."
- Tailscale operator is used for private/internal access only (e.g. DBeaver
  → Postgres), annotated per-Service with `tailscale.com/expose: "true"` and
  `tailscale.com/hostname: dumpnet-<service>`. `ingressClass` is disabled on
  the operator so it doesn't try to manage public ingresses too.
- DNS records are Terraform-managed (`dns_records` list in
  `terraform.tfvars`) — add new subdomains there, not manually in Route53
  console.

## Container images

- Prefer official upstream images. When a custom image must be built (e.g.
  `mcp-auth-proxy`), it lives under `images/<name>/Dockerfile` in this same
  repo — no separate repo for a thin wrapper Dockerfile.
- Use multi-stage builds; final stage should be `scratch` or
  `distroless` for Go binaries — keep images small, self-hosted Forgejo has a
  registry size limit (`nginx.clientMaxBodySize` + Forgejo's own
  `packages.MAX_BLOB_SIZE`, both had to be raised from defaults on the
  NixOS box).
- Custom images push to the **Forgejo container registry**
  (`forge.keane.sh/ian/<image>`), not ECR. ECR was set up once and
  deliberately removed — an EC2/Talos node can't easily pull from ECR without
  baking a system extension into a custom AMI via Image Factory, which is
  more infra than it's worth for a personal cluster. Forgejo + the node's
  default pull path works fine and stays consistent with "no unnecessary
  centralized services."
- `registry.host` / `registry.user` are values in the root `values.yaml` —
  reference them, don't hardcode `forge.keane.sh`/`ian` in new charts.

## Databases

- One shared Postgres in the `data` group/namespace (`postgres`), used by
  multiple services (kan, future services). Don't spin up a dedicated
  Postgres per service.
- New service databases: connect via DBeaver (Tailscale-exposed
  `dumpnet-postgres:5432`) and `CREATE DATABASE <name>;` manually — there's
  no automated database-per-service provisioning yet. Password comes from
  `postgres.password` in the `dumpnet` secret (same user/password works for
  every DB on the instance, it's one Postgres server).
- Migration Jobs (e.g. `kan-migrate`) should NOT use ArgoCD `PreSync` hooks —
  hooks and sync-wave ordering don't compose the way you'd expect ExternalSecret
  creation vs. hook timing. Use plain `Job` resources with `sync-wave`
  annotations instead (ExternalSecret at wave `-1`, migration Job at wave
  `1`), and set `ttlSecondsAfterFinished` so completed jobs clean themselves up.

## Email

- Outbound email (magic links etc.) goes through SES SMTP
  (`email-smtp.us-east-1.amazonaws.com`), domain `dumpnet.chat` (verified via
  Terraform-managed DKIM/TXT records). `keane.sh` is reserved for the
  Fastmail alias — don't touch its DNS or try to send from `@keane.sh`.
- SES starts in sandbox mode — verify individual recipient addresses via
  `aws ses verify-email-identity` until production access is granted.
- Check upstream app source (not assumptions) for the actual expected env
  var names before wiring up SMTP — e.g. kan uses `SMTP_HOST` /
  `SMTP_PORT` / `SMTP_USER` / `SMTP_PASSWORD` / `SMTP_SECURE` /
  `EMAIL_FROM`, not `EMAIL_SERVER_*`. Wrong var names fail silently/weirdly
  (e.g. connects to `127.0.0.1:465` when nothing is configured) rather than
  erroring clearly.

## Operational workflow

- `make apply` is a **two-phase** terraform apply (first targets
  `talos_cluster_kubeconfig.this` and its deps, then a full apply) — the
  Terraform `helm`/`kubernetes` providers can't initialize before the
  cluster exists. Don't try to collapse this into one `terraform apply`.
- After any fresh `apply`: `make post-apply` (waits for node, imports
  ingress-nginx namespace state if needed, runs `make bootstrap`, builds/pushes
  any custom images). Then DNS/cert issuance takes a few minutes.
- `make clean` before `make destroy` when doing a full from-zero rebuild —
  force-deletes the Secrets Manager secret (avoids the 30-day recovery
  window blocking recreation) and clears stale kubectl/talosctl contexts.
  It does NOT touch Route53 (Terraform-managed, fine to destroy/recreate).
- After any pod-affecting change to an `ExternalSecret`, the **existing**
  pod does not pick up new secret data automatically — force ESO to
  re-sync (`kubectl annotate externalsecret <name> -n <ns> force-sync=$(date
  +%s) --overwrite`) and then delete/restart the pod. `kubectl rollout
  restart` alone is not reliably enough — prefer `kubectl delete pod` for a
  clean restart, especially if the deployment spec itself changed and
  ArgoCD hasn't synced yet (check `kubectl get deployment ... -o
  jsonpath='{.spec.template.spec.containers[0].args}'` to confirm before
  assuming a restart will fix anything).
- When something is "OutOfSync" in ArgoCD for no apparent reason, actually
  look at the diff (`kubectl describe app <name> -n argocd`) rather than
  guessing — several past sessions burned significant time on guessed fixes
  (mergePolicy, engineVersion, type placement) before checking the real
  diff.
- Prefer diagnosing root cause over reflexive retries. This repo's history
  includes multiple incidents where the same command was rerun repeatedly
  without new information — check logs/state first, form a hypothesis,
  test it once.

## Documentation

- Keep `README.md` up to date for: first-time setup, secrets approach,
  day-to-day ops, Makefile reference, forking/multi-environment notes. If a
  new operational gotcha is discovered (like the two-phase apply, or
  `make clean`), add it to the README, not just this file.
