@@ -0,0 +1,13 @@
+---
+'@objectstack/runtime': minor
+'@objectstack/cli': patch
+---
+
+fix(runtime,cli): an upper-case `FILE:` database URL opens the file its lower-case spelling opens, `file://NAME` opens `NAME` on both hosts, and the URL-to-filename rule is exported as `sqliteFilenameFromUrl`
+
+Clause-②: yes (widening)
+
+- **`FILE:` is stripped case-insensitively.** The standalone host classified `FILE:./app.db` as SQLite case-insensitively but stripped the prefix case-sensitively, so the prefix stayed in the file name: `OS_DATABASE_URL=FILE:./app.db` created a directory literally named `FILE:.` and put the database inside it, and `File:///tmp/app.db` was refused as an unsupported `File://` scheme. Both now open the file the lower-case spelling opens (`./app.db`, `/tmp/app.db`), as the `sqlite-wasm` path already did. Lower-case `file:` URLs and bare paths are unchanged.
+- **New export: `sqliteFilenameFromUrl(url, kind)`** from `@objectstack/runtime`, `kind` being `'sqlite'` or `'sqlite-wasm'`. It is the one rule that turns a SQLite database URL (after `normalizeDatabaseUrl`) into a file name: `file:` / `file://` stripped case-insensitively, plus `wasm-sqlite:` for the WASM kind. For `'sqlite'` it throws a plain `Error` on a URL that is not a file path, naming the URL's scheme and never the URL. Nothing is removed.
+- **`os serve`'s legacy storage path (`OS_MODE=off`, `bootMode: 'off'`, or a host config) turns a SQLite URL into a file by that same rule**, so both hosts open one file per URL. It used to strip only a lower-case `file:`: `OS_DATABASE_URL=file://NAME` opened `//NAME` at the filesystem root, where the standalone host opens `./NAME`, and `FILE:./app.db` made a `FILE:.` directory there too. `file:///abs/app.db` opens `/abs/app.db`; `sqlite:` / `sqlite://` URLs are unchanged.
+- **What that rule refuses, the legacy path now refuses too, and fatally**, with the standalone host's own sentence (it names the URL's scheme, never the URL): an explicit `OS_DATABASE_DRIVER=sqlite` over a server URL such as `postgres://user:password@host/db`, which used to create directories named after the URL, credentials included, and a `file:` URL that names no file, which used to declare a database with an empty file name. Fix: point `OS_DATABASE_URL` at a file (`file:./app.db`), or select the driver the URL is for. The undocumented `sql://` prefix that path also stripped under an explicit `sqlite` selection is refused the same way; write `file:` instead. A blank `OS_DATABASE_URL` under an explicit `sqlite` selection is read as absent (`:memory:`), as an absent one always was.
@@ -533,15 +533,27 @@ describe('the OS_DATABASE_URL door: both hosts, one verdict per URL, dev and pro
     }
   });
 
-  // `sqlite:` / `sqlite://` are aliases of `file:` on both hosts, by ONE rule —
-  // the runtime host's `normalizeDatabaseUrl`, which the CLI host calls. Both
-  // hosts must name the same FILE: `sqlite://x.db` used to open `//x.db` (the
-  // filesystem root) on the CLI host while the runtime host opened `x.db`.
+  // `sqlite:` / `sqlite://` are aliases of `file:` on both hosts, and a `file:`
+  // URL becomes a file name by ONE rule — the runtime host's
+  // `normalizeDatabaseUrl` and `sqliteFilenameFromUrl`, both of which the CLI
+  // host calls. Both hosts must name the same FILE: `sqlite://x.db` and
+  // `file://x.db` used to open `//x.db` (the filesystem root) on the CLI host
+  // while the runtime host opened `x.db`, and `FILE:./x.db` kept its upper-case
+  // prefix as part of the file name on both, making a `FILE:.` directory. The
+  // lower-case `file:` and bare-path rows are the CONTROL.
   it.each([
     ['sqlite://x.db', 'x.db', 'sqlite'],
     ['sqlite:x.db', 'x.db', 'sqlite'],
     ['sqlite:///var/lib/objectstack/x.db', '/var/lib/objectstack/x.db', 'sqlite'],
     ['sqlite://x.wasm.db', 'x.wasm.db', 'sqlite-wasm'],
+    ['file://x.db', 'x.db', 'sqlite'],
+    ['file:///var/lib/objectstack/x.db', '/var/lib/objectstack/x.db', 'sqlite'],
+    ['file://x.wasm.db', 'x.wasm.db', 'sqlite-wasm'],
+    ['FILE:./x.db', './x.db', 'sqlite'],
+    ['File:///var/lib/objectstack/x.db', '/var/lib/objectstack/x.db', 'sqlite'],
+    ['FILE:./x.wasm.db', './x.wasm.db', 'sqlite-wasm'],
+    ['file:./x.db', './x.db', 'sqlite'],
+    ['./x.db', './x.db', 'sqlite'],
   ])('both hosts open %s as the file %s (%s), in dev and prod', (url, file, kind) => {
     process.env.OS_DATABASE_URL = url;
     const runtime = resolveStandaloneDatabase({ artifactPath: '/nonexistent/objectstack.json' });
@@ -553,4 +565,50 @@ describe('the OS_DATABASE_URL door: both hosts, one verdict per URL, dev and pro
       expect(definition!.config.filename, `the CLI host's file for ${url} (isDev=${isDev})`).toBe(runtime.sqliteFile);
     }
   });
+
+  // What that rule refuses, both hosts refuse, with ONE sentence that names the
+  // scheme and never the URL — the CLI host's is the runtime host's minus its
+  // `[StandaloneStack]` tag, as for the retired engine above — and the CLI
+  // host's refusal is typed, the class serve.ts makes fatal (it swallows every
+  // other construction error). Two
+  // inputs reach it: an explicit sqlite selection over a server URL, which the
+  // CLI host used to open as a file at a path made of the URL, credentials
+  // included, and a `file:` that names no file.
+  it.each([
+    ['sqlite', 'postgres://PLACEHOLDER-USER:PLACEHOLDER-SECRET@127.0.0.1:5432/db', 'its scheme is "postgres://"'],
+    [undefined, 'file:', 'it names no file after "file:"'],
+    [undefined, 'FILE:', 'it names no file after "file:"'],
+  ])('both hosts REFUSE driver %s over %s, in dev AND in prod, with one sentence', (driver, url, why) => {
+    if (driver) process.env.OS_DATABASE_DRIVER = driver;
+    const runtime = runtimeUrlVerdict(url);
+    expect(runtime.accepted, `the runtime host accepted ${url}`).toBe(false);
+    const sentence = (runtime as { message: string }).message;
+    expect(sentence).toContain(why);
+    for (const isDev of [false, true]) {
+      let error: unknown;
+      try {
+        resolveStorageDefinition(resolveDriverType(driver, url), { databaseUrl: url, isDev });
+      } catch (err) {
+        error = err;
+      }
+      expect(error, `the CLI host (isDev=${isDev}) did not refuse ${url} by type`).toBeInstanceOf(UnsupportedDriverError);
+      expect((error as UnsupportedDriverError).recognized).toBe(true);
+      expect((error as UnsupportedDriverError).driverType).toBe('sqlite');
+      expect((error as Error).message).toBe(sentence.replace(/^\[StandaloneStack\] /, ''));
+      expect((error as Error).message).not.toBe(sentence);
+      expect((error as Error).message).not.toContain('PLACEHOLDER');
+    }
+  });
+
+  // CLI host only: under an explicit sqlite selection a blank URL is the absent
+  // URL, `:memory:`, never a file named by whitespace — blank is absent, as this
+  // host's URL inference reads it. The runtime host's absent URL is its default
+  // file, a different answer for absence that this pin does not judge.
+  it.each(['', '   '])('the CLI host reads the blank URL %j under an explicit sqlite selection as :memory:', (url) => {
+    for (const isDev of [false, true]) {
+      const definition = resolveStorageDefinition(resolveDriverType('sqlite', url), { databaseUrl: url, isDev });
+      expect(definition!.driverId).toBe('sqlite');
+      expect(definition!.config.filename).toBe(':memory:');
+    }
+  });
 });
@@ -106,6 +106,7 @@ import {
   namesRetiredMemoryEngine,
   normalizeDatabaseUrl,
   retiredMemoryEngineMessage,
+  sqliteFilenameFromUrl,
   type LoadTursoDriverFactoryOptions,
 } from '@objectstack/runtime';
 import {
@@ -527,13 +528,11 @@ export function resolveStorageDefinition(
   }
 
   if (kind === 'sqlite') {
-    // `sqlite:` and `sqlite://` are aliases of `file:`, translated by the runtime
-    // host's own rule (`normalizeDatabaseUrl`) rather than a second copy of it,
-    // so both hosts open one file: `sqlite://x.db` is `x.db`, never `//x.db`
-    // (the filesystem root), and `sqlite:///abs/x.db` is `/abs/x.db`.
-    const filePath = normalizeDatabaseUrl(databaseUrl ?? ':memory:')
-      .replace(/^file:/, '')
-      .replace(/^sql:\/\//, '');
+    // The runtime host's file for this URL ({@link sqliteFileFor}), never a
+    // second copy of its rule: `sqlite://x.db` and `file://x.db` are `x.db`,
+    // never `//x.db` (the filesystem root), `file:///abs/x.db` is `/abs/x.db`,
+    // and `FILE:./x.db` is `./x.db`.
+    const filePath = sqliteFileFor(databaseUrl, 'sqlite');
     return {
       driverId: 'sqlite',
       config: { filename: filePath, ...devAutoMigrateConfig('sqlite', isDev) },
@@ -548,10 +547,9 @@ export function resolveStorageDefinition(
   }
 
   if (kind === 'sqlite-wasm') {
-    // The same alias rule as the sqlite arm: `sqlite://x.wasm.db` is `x.wasm.db`.
-    const filePath = normalizeDatabaseUrl(databaseUrl ?? ':memory:')
-      .replace(/^file:/, '')
-      .replace(/^wasm-sqlite:\/\//, '');
+    // The same rule as the sqlite arm, `wasm-sqlite://` included:
+    // `sqlite://x.wasm.db` and `file://x.wasm.db` are `x.wasm.db`.
+    const filePath = sqliteFileFor(databaseUrl, 'sqlite-wasm');
     return {
       driverId: 'sqlite-wasm',
       // `persist` passthrough: the CLI kept `on-disconnect` semantics here
@@ -629,6 +627,40 @@ export function resolveStorageDefinition(
   return null;
 }
 
+/**
+ * The SQLite file a `default` definition opens for this URL — the runtime
+ * host's answer, by the runtime host's rule: `normalizeDatabaseUrl` (`sqlite:` /
+ * `sqlite://` are `file:`), then `sqliteFilenameFromUrl` (`file:` / `file://`,
+ * and `wasm-sqlite:` for the WASM kind, stripped case-insensitively). This file
+ * used to keep its own copy, a case-sensitive `/^file:/` strip, so
+ * `file://NAME` opened `//NAME` at the filesystem root, where the runtime host
+ * opens `NAME`, and `FILE:./x.db` made a directory named `FILE:.`.
+ *
+ * An absent or blank URL is `:memory:`: blank is absent, as
+ * {@link inferDriverTypeFromUrl} reads it, never a file named by whitespace.
+ *
+ * A URL the rule refuses is re-raised as {@link UnsupportedDriverError} with
+ * the runtime host's own sentence, which names the scheme and never the URL,
+ * minus its `[StandaloneStack]` tag — the shape this host's retired-engine
+ * refusal already has (`driver-vocabulary-parity.test.ts` holds both).
+ * Two inputs reach that: an explicit `sqlite` selection over a server URL
+ * (`OS_DATABASE_DRIVER=sqlite` beside `postgres://user:password@…`), and a
+ * `file:` that names no file. Both used to build a definition: the first opened
+ * a file at a path made of the URL, credentials included, and the second
+ * declared an empty file name. The type is
+ * what makes the refusal fatal: `serve.ts` re-throws this class and swallows
+ * every other construction error, so a plain `Error` would boot with no
+ * storage at all.
+ */
+function sqliteFileFor(databaseUrl: string | undefined, kind: 'sqlite' | 'sqlite-wasm'): string {
+  const url = normalizeDatabaseUrl(databaseUrl?.trim() ? databaseUrl : ':memory:');
+  try {
+    return sqliteFilenameFromUrl(url, kind);
+  } catch (err) {
+    throw new UnsupportedDriverError(kind, (err as Error).message.replace(/^\[StandaloneStack\] /, ''));
+  }
+}
+
 /**
  * Load the OPTIONAL libSQL/Turso driver package and wrap it as the host driver
  * factory `DefaultDatasourcePlugin` accepts (#5602).
 
@@ -8,7 +8,7 @@ export { Runtime } from './runtime.js';
 export type { RuntimeConfig } from './runtime.js';
 
 // Export Standalone Stack
-export { createStandaloneStack, resolveObjectStackHome, resolveStandaloneDatabase } from './standalone-stack.js';
+export { createStandaloneStack, resolveObjectStackHome, resolveStandaloneDatabase, sqliteFilenameFromUrl } from './standalone-stack.js';
 export type { StandaloneStackConfig, StandaloneStackResult, ResolvedStandaloneDatabase } from './standalone-stack.js';
 
 // The dev schema self-heal decision (#21733) — public because `@objectstack/cli`
 
@@ -335,6 +335,36 @@ describe('resolveStandaloneDatabase — #6469 behaviours through the migrate sea
     expect(r.sqliteFile).toBe(join(root, 'a.db'));
   });
 
+  // `file:` is classified case-insensitively, so it is stripped case-insensitively
+  // too: an upper-case prefix the strip kept became part of the file name, and
+  // `FILE:./app.db` made a directory literally named `FILE:.`. Every row names
+  // the file its lower-case spelling names; the lower-case and bare rows are the
+  // CONTROL, unchanged.
+  it.each([
+    ['FILE:./x.db', './x.db', 'sqlite'],
+    ['File:///tmp/x.db', '/tmp/x.db', 'sqlite'],
+    ['FILE://x.db', 'x.db', 'sqlite'],
+    ['file:./x.db', './x.db', 'sqlite'],
+    ['file:///tmp/x.db', '/tmp/x.db', 'sqlite'],
+    ['file://x.db', 'x.db', 'sqlite'],
+    ['./x.db', './x.db', 'sqlite'],
+    ['/tmp/x.db', '/tmp/x.db', 'sqlite'],
+    ['FILE:./x.wasm.db', './x.wasm.db', 'sqlite-wasm'],
+  ])('%s opens the sqlite file %s (%s)', (url, file, driver) => {
+    const r = resolveStandaloneDatabase({ databaseUrl: url });
+    expect(r.driver).toBe(driver);
+    expect(r.sqliteFile).toBe(file);
+  });
+
+  it('an upper-case FILE: that names no file is refused like file:, never opened as a file named "FILE:"', () => {
+    let err: unknown;
+    try { resolveStandaloneDatabase({ databaseUrl: 'FILE:' }); } catch (e) { err = e; }
+    expect(err).toBeInstanceOf(Error);
+    expect((err as Error).constructor).toBe(Error);
+    expect((err as Error).message).toContain('sqlite driver was selected but the URL does not look like a file path');
+    expect((err as Error).message).toContain('it names no file after "file:"');
+  });
+
   it('still refuses a genuinely unsupported scheme, message intact', () => {
     expect(() => resolveStandaloneDatabase({ databaseUrl: 'redis://localhost:6379' }))
       .toThrow(/Unsupported database URL scheme/);
 
@@ -15,7 +15,7 @@
 // owner-only `member_default`.
 
 import { describe, it, expect, beforeAll, afterAll } from 'vitest';
-import { mkdtempSync, rmSync, writeFileSync } from 'node:fs';
+import { mkdtempSync, readdirSync, rmSync, writeFileSync } from 'node:fs';
 import { tmpdir } from 'node:os';
 import { join } from 'node:path';
 import { createStandaloneStack } from './standalone-stack.js';
@@ -397,6 +397,27 @@ describe('createStandaloneStack — default datasource declared, built via the s
     expect(r.titles).toContain('hello-driver');
   }, BOOT_TIMEOUT);
 
+  // An upper-case `FILE:` is the same file as `file:`, and the boot's directory
+  // preparation creates no `FILE:` directory on the way. Run from an empty cwd:
+  // the prefix used to survive into the relative filename, so the directory it
+  // made landed beside the process.
+  it('FILE: → declares the same file as file: and creates no FILE: directory', async () => {
+    const cwd = process.cwd();
+    const work = mkdtempSync(join(tmpdir(), 'os-file-url-case-'));
+    process.chdir(work);
+    try {
+      const upper = defaultDefOf(await createStandaloneStack({ databaseUrl: 'FILE:./upper/x.db' })).def;
+      const lower = defaultDefOf(await createStandaloneStack({ databaseUrl: 'file:./upper/x.db' })).def;
+      expect(upper.driver).toBe('sqlite');
+      expect(upper.config?.filename).toBe('./upper/x.db');
+      expect(upper.config?.filename).toBe(lower.config?.filename);
+      expect(readdirSync(work).filter((name) => /^file:/i.test(name))).toEqual([]);
+    } finally {
+      process.chdir(cwd);
+      rmSync(work, { recursive: true, force: true });
+    }
+  }, BOOT_TIMEOUT);
+
   it('databaseDriver:sqlite-wasm → declares driver "sqlite-wasm"; factory builds SqliteWasmDriver that round-trips', async () => {
     const r = await definitionRoundTrip({ databaseDriver: 'sqlite-wasm', databaseUrl: `file:${join(dir, 'wasm.db')}` });
     expect(r.driverId).toBe('sqlite-wasm');
 
@@ -582,14 +582,31 @@ function refuseRetiredMemoryEngine(
     throw new Error(`[StandaloneStack] ${retiredMemoryEngineMessage(selection)}`);
 }
 
-/** URL→filename for the two sqlite kinds. Throws on a URL that isn't a path. */
-function sqliteFilenameFromUrl(dbUrl: string, kind: 'sqlite' | 'sqlite-wasm'): string {
+/**
+ * URL→filename for the two sqlite kinds: the ONE rule both hosts turn a SQLite
+ * database URL into a file with. Throws on a URL that isn't a path.
+ *
+ * Takes the URL as {@link resolveStandaloneDatabase} has it, i.e. after
+ * `normalizeDatabaseUrl` (`sqlite:` / `sqlite://` are already `file:`).
+ * `file:` and `file://` are stripped case-insensitively on BOTH kinds, as
+ * {@link detectDriverFromUrl} classifies them (`/^file:/i`): a prefix the
+ * classifier accepts and this strip kept became part of the filename, so
+ * `FILE:./app.db` opened `./FILE:./app.db` and the boot's directory creation
+ * made a `FILE:.` directory — the "bogus directory from a URL" this module's
+ * header rules out.
+ *
+ * Exported because the CLI host (`resolveStorageDefinition` in
+ * `@objectstack/cli`'s `utils/storage-driver.ts`) calls it rather than keeping
+ * a second copy; its copy stripped only `/^file:/`, so `file://NAME` opened
+ * `//NAME` at the filesystem root there while this host opened `NAME`.
+ */
+export function sqliteFilenameFromUrl(dbUrl: string, kind: 'sqlite' | 'sqlite-wasm'): string {
     if (kind === 'sqlite-wasm') {
         return dbUrl
             .replace(/^wasm-sqlite:(\/\/)?/i, '')
             .replace(/^file:(\/\/)?/i, '') || ':memory:';
     }
-    const filename = dbUrl.replace(/^file:(\/\/)?/, '');
+    const filename = dbUrl.replace(/^file:(\/\/)?/i, '');
     const scheme = urlSchemeOf(filename);
     if (!filename || scheme) {
         // Names the scheme, never the URL ({@link urlSchemeOf}). This is the