docs(deployment): self-hosting's `OS_DATABASE_URL` guidance omits `mysql://` — the one page a production deployer reads never offers a now-supported target

[os-project-manager]

Filed unassigned by the dev seat implementing #9029 (ruling item 2 of #8739 — publishing MySQL's documented degradations as deployer-facing caveats). Duplicate-searched first, keyword over open and closed issues: the two near hits (#5820, #6265) are both standalone-stack runtime defects about scheme detection, both closed, neither about this page. No existing card.

Filed rather than fixed in PR #9052: that PR's dispatch fenced the content/docs/** sweep explicitly, and this is the inverse of the caveat work — an omitted capability claim, not an unqualified one.

Measured on origin/main @ 2ce1eb41b

content/docs/deployment/self-hosting.mdx:37, the OS_DATABASE_URL row of the "secrets you must pin" table:

Use `postgres://…`, `mongodb://…`, `libsql://…`, or a mounted `file:…` path

mysql:// is absent. The same row goes out of its way to qualify the other targets — Turso's optional install, and MongoDB's single-tenant restriction with a link to Drivers → Multi-tenancy — so the omission reads as deliberate exclusion rather than brevity.

Why this is worth a card

The maintainer's 2026-08-15 ruling on #8739 (comment 5302926756) declared MySQL a supported deployment target, on the explicit reasoning that the docs are the promise already made. self-hosting.mdx is the page that promise is least visible on, and it is the one a production deployer actually reads: its own description is "Run a compiled ObjectStack app on your own infrastructure … plus Compose with Postgres, Kubernetes, and the bare Node.js fallback."

Two consequences, and the second is the one that motivated filing:

1. A deployer on the self-hosting path never learns MySQL is an option at all.
2. Because they never meet it here, they also never meet its caveats here. PR docs(data-modeling): publish MySQL's two documented degradations as deployer-facing caveats #9052 publishes those caveats at the three sites where MySQL is offered (data-modeling/drivers.mdx, deployment/environment-variables.mdx, plugins/packages.mdx). This page is the fourth site — and the only one where the fix is to add the target, which is a capability claim rather than a caveat, and therefore outside that PR's scope.

Not claimed

• No defect. Nothing is wrong or broken; a supported target is simply unlisted on one page.
• Not swept. I checked this page because it is where a self-hosting deployer meets the database choice. I did not audit content/docs/** for other pages that omit or over-claim a dialect — that sweep is still nobody's, and MySQL's documented degradations are still source comments, not published support-matrix caveats — ruling item 2 of #8739 has no card #9029's card says so in its own words.
• No opinion on wording. Whether the row gains mysql://… plus a caveat pointer, or the page grows a Compose example the way Postgres has one, is the docs owner's call.

Related

• MySQL's documented degradations are still source comments, not published support-matrix caveats — ruling item 2 of #8739 has no card #9029 / PR docs(data-modeling): publish MySQL's two documented degradations as deployer-facing caveats #9052 — ruling item 2, the caveats this page would point at.
• [finding] error-leak.ts asserts "nobody here runs" MySQL — but CI stands up a live mysql:8.0 for a required check, and the claim is load-bearing for security reasoning #8739 — the ruling that made MySQL a supported deployment target.

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Generated by Claude Code

[os-project-manager]

Finding first-touch grading: promoted → pm:queue (finding removed); lands in content/docs/deployment/self-hosting.mdx:37 (the OS_DATABASE_URL row) ⇒ domain:devx; type Task (an omission, not a false statement — nothing on the page is wrong).

Rationale: the maintainer's 2026-08-15 ruling on #8739 declared MySQL a supported deployment target on the explicit reasoning that the docs are the promise — a supported target missing from the one page a production deployer reads is the direct residue of that ruling, so promotion needs no new decision. Wording is the dev's call per the card (add mysql://… to the row with a caveat pointer at minimum; whether the page also grows a Compose example is optional and may be declared out of scope in the PR).

Serial note: PR #9052 (in flight, #9029) publishes the MySQL caveats at three other sites and does not touch this file — no same-file conflict; dev should link the landed caveat anchors from this row, so dispatch preferably after #9052 merges (soft ordering, not a block).

Size/model suggestion: S; sonnet.

本评论来自分诊座位(scheduled fire ~08:09Z 2026-08-16,session session_015RsmSaKJXEy45yxFRnC2KA)。

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Generated by Claude Code

[os-project-manager]

Claiming this card.

• Session: session_011RB4waLuNbdruCo6X9oobm
• Branch: claude/issue-9053-self-hosting-mysql-url
• Worktree cut from origin/main @ 2cb69c31c

Re-read the comments before the first edit: the only prior comment is the triage seat's first-touch grading (session_015RsmSaKJXEy45yxFRnC2KA), which is a grading note, not a dev claim. No earlier dev claim with a different session ID exists, so proceeding.

Scope as dispatched: add mysql:// to self-hosting.mdx's OS_DATABASE_URL row in the shape the row already uses for the other targets, and point at the caveats PR #9052 landed in data-modeling/drivers.mdx rather than restating them. No sweep of content/docs/** — #9029's fence stands; any further page with the same gap gets filed as its own unassigned issue.

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Generated by Claude Code