# REPORT — vaultwarden F1 fix: `_ENABLE_SMTP` boot-gate (2026-07-06)

**Class:** implementation (campaign-finding fix; push = deploy).
**Baseline:** `main` @ `13eedb1` → (this commit). Provenance: felhom.eu
`documentation/audits/CAMPAIGN-nomercy-2026-07-06.md` finding **F1** (pilot-blocking: every fresh
vaultwarden deploy with app-email off — the default — crash-loops).

## Corrected root cause (the campaign report's hypothesis was wrong)

Not "shim sets SMTP_FROM without SMTP_HOST" — with app-email off the shim injects **nothing**. The
crasher: the template always defines `SMTP_HOST=${SMTP_HOST:-}` and `SMTP_FROM=${SMTP_FROM:-}`;
vaultwarden's `get_env_str_value` returns `Some("")` for a defined-empty var (**empty counts as
set**), and with `_enable_smtp` defaulting `true` upstream, its validation
`smtp_host.is_some() == smtp_from.is_empty()` → `true == true` → config error → exit → crash-loop.
The old template comment ("empty SMTP_HOST = mail stays disabled") was wrong for this image.

## Empirical probe (mandatory gate, run on 180 against the pinned image BEFORE editing)

| Probe | Env | Result |
|---|---|---|
| P1 (pre-fix shape) | `SMTP_HOST=` `SMTP_FROM=` (defined-empty) | **exit 12** — *"Both `SMTP_HOST` and `SMTP_FROM` need to be set for email support without `USE_SENDMAIL`"* (exact campaign error) — the image-level red-proof |
| P2 (fix, OFF) | + `_ENABLE_SMTP=false` | **boots** — "Rocket has launched", running |
| P3 (fix, ON) | `_ENABLE_SMTP=true` + host + from | **boots** — running (no SMTP connect at boot) |

(P2/P3 needed `I_REALLY_WANT_VOLATILE_STORAGE=true` to bypass the unrelated no-volume guard in the
bare `docker run`; P1 control re-run with it still crashes on the SMTP error, isolating the cause.)
Logs: DooPlex `~/campaign-nomercy-2026-07-05/evidence/PROBE-F1/`.

## Changes

- `templates/vaultwarden/docker-compose.yml` — `_ENABLE_SMTP=${_ENABLE_SMTP:-false}` added to the
  SMTP group; the wrong comment replaced with the empty-counts-as-set TRAP note (+ config.json
  admin-panel precedence note). Nothing else touched.
- `templates/vaultwarden/.felhom.yml` — `smtp_mapping.extra: _ENABLE_SMTP: "true"` (rides the
  existing `smtpEnv` extra loop; zero controller change).
- `REUSE.md` — TRAP appended to the App-email row: strict images need the enable-flag pattern;
  boot-prove fresh email-off deploys for every new smtp-mapped app.
- `CHANGELOG.md` — entry incl. the sweep note.

## Sweep note (documentation only, no edits)

calcom, gitea, mealie, nextcloud, rallly (and gitea's `GITEA__mailer__SMTP_ADDR=${...:-}`) are
**boot-proven tolerant** of defined-empty mail env — all ran healthy as fresh email-off deploys in
the campaign. Vaultwarden was the only strict image.

## Validation

- Probe gate P1/P2/P3 above (image level).
- Live pipeline validation (Scenario A fresh email-off deploy healthy; Scenario B toggle ON→OFF
  regression) executed as part of the controller v0.101.0 deployment — see
  felhom-controller/REPORT.md for the live evidence.