@@ -0,0 +1,16 @@
+---
+'@objectstack/driver-sql': patch
+---
+
+fix(driver-sql): a SQLite database file the driver cannot create or open fails `connect()` at once, naming the file and the operating system's error (#23696)
+
+Clause-②: no
+
+A declared SQLite datasource whose `config.filename` lay under a directory the operating system will not make (for example `/proc/x/ds.db`) never finished connecting. The driver made the directory with Node's recursive `mkdir`, which loops without end on such a path: `mkdir` of the level answers `ENOENT`, its parent answers `EEXIST`, and it retries, about 1,600 failing calls a second, all system CPU. The boot was then refused only by a plugin start timeout (30 s, or 120 s when a `datasourceMapping` rule routes to the datasource), and that message named neither the datasource, the path nor the error. The same happened to the host's own database when `OS_DATABASE_URL=file:` named such a path.
+
+**What changes**
+
+- The directory is made by a walk bounded by the path's depth, one non-recursive `mkdir` per missing level. The first level the operating system refuses fails `connect()` with a `SqliteDatabaseFileError` that names the file, the directory and the cause (`ENOENT`, `EACCES`, `ENOTDIR`, …).
+- A file SQLite itself cannot open (`SQLITE_CANTOPEN`, for example a filename that is a directory) now fails `connect()` the same way. Before, the error was logged as a warning and `connect()` resolved, so the datasource counted as connected while it could not answer one query. A native-addon load failure keeps its warning and the step-down to wasm SQLite.
+
+The boot's existing connect refusal (ADR-0062 D5) carries this message, so `objectstack serve` on such a config now prints, at once, `datasource 'primary': connect failed — SQLite database file '/proc/x/ds.db' cannot be created: its directory '/proc/x' could not be made: ENOENT: no such file or directory, mkdir '/proc/x'`. No configuration key or accepted value changes. A path the operating system can create still connects.
@@ -0,0 +1,111 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+
+/**
+ * A SQLite file the driver cannot create or open fails `connect()` at once,
+ * naming the file and the operating system's answer (#23696).
+ *
+ * Before: a filename under `/proc/<missing>/` never finished connecting. Node's
+ * recursive mkdir loops on that path (`mkdir` of the level answers `ENOENT`,
+ * its parent answers `EEXIST`, retry) and burns system CPU, so a declared
+ * datasource there was refused only by a plugin start timeout that named
+ * neither the datasource nor the path. A filename SQLite itself cannot open
+ * (`SQLITE_CANTOPEN`) was logged and swallowed: `connect()` resolved and the
+ * datasource counted as connected while it could answer no query.
+ *
+ * What the boot prints is `datasource '<name>': connect failed — <reason>`
+ * (ADR-0062 D5, the connection service); `<reason>` is this error's message,
+ * so the pins here hold the file and the cause in it.
+ */
+
+import { describe, it, expect, beforeEach, afterEach } from 'vitest';
+import { existsSync, mkdirSync, mkdtempSync, rmSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { SqlDriver } from './sql-driver.js';
+import { SqliteDatabaseFileError } from './sqlite-database-file.js';
+
+/** The refusal must arrive within this; before the fix it never arrived. */
+const WITHIN_MS = 1_000;
+
+const drivers: SqlDriver[] = [];
+function make(filename: string): SqlDriver {
+  const d = new SqlDriver({ client: 'better-sqlite3', connection: { filename }, useNullAsDefault: true });
+  drivers.push(d);
+  return d;
+}
+
+/** `connect()`'s rejection, or a failure naming the wait when it never settles. */
+async function refusalOf(driver: SqlDriver): Promise<{ error: unknown; ms: number }> {
+  const t0 = Date.now();
+  let timer: ReturnType<typeof setTimeout> | undefined;
+  const never = new Promise<never>((_, reject) => {
+    timer = setTimeout(() => reject(new Error(`connect() had not settled after ${5 * WITHIN_MS} ms`)), 5 * WITHIN_MS);
+  });
+  try {
+    await Promise.race([driver.connect(), never]);
+  } catch (error) {
+    if ((error as Error).message.startsWith('connect() had not settled')) throw error;
+    return { error, ms: Date.now() - t0 };
+  } finally {
+    clearTimeout(timer);
+  }
+  throw new Error('connect() resolved for a file that cannot be created or opened');
+}
+
+function expectNamedRefusal(error: unknown, filename: string, code: string): void {
+  expect(error).toBeInstanceOf(SqliteDatabaseFileError);
+  const e = error as SqliteDatabaseFileError;
+  expect(e.code).toBe(code);
+  expect(e.filename).toBe(filename);
+  expect(e.message).toContain(filename);
+  expect(e.message).toContain((e.cause as Error).message);
+}
+
+let dir: string;
+beforeEach(() => { dir = mkdtempSync(join(tmpdir(), 'os-23696-')); });
+afterEach(async () => {
+  await Promise.all(drivers.splice(0).map((d) => d.disconnect().catch(() => {})));
+  rmSync(dir, { recursive: true, force: true });
+});
+
+describe('SqlDriver.connect — a SQLite file that cannot be created or opened (#23696)', () => {
+  it.runIf(existsSync('/proc/self'))(
+    'refuses a directory the OS will not make (/proc/<missing>/) at once — the shape that looped',
+    async () => {
+      const filename = `/proc/os-23696-${process.pid}/a/ds.db`;
+      const { error, ms } = await refusalOf(make(filename));
+      expectNamedRefusal(error, filename, 'ENOENT');
+      expect(ms).toBeLessThan(WITHIN_MS);
+    },
+  );
+
+  it('refuses a path through a regular file, naming it', async () => {
+    writeFileSync(join(dir, 'plain'), '');
+    const through = join(dir, 'plain', 'sub', 'ds.db');
+    const throughRefusal = await refusalOf(make(through));
+    expectNamedRefusal(throughRefusal.error, through, 'ENOTDIR');
+    expect(throughRefusal.ms).toBeLessThan(WITHIN_MS);
+
+    // The file holds the directory's own name.
+    const at = join(dir, 'plain', 'ds.db');
+    const atRefusal = await refusalOf(make(at));
+    expectNamedRefusal(atRefusal.error, at, 'EEXIST');
+    expect(atRefusal.ms).toBeLessThan(WITHIN_MS);
+  });
+
+  it('refuses a file SQLite cannot open (SQLITE_CANTOPEN) instead of resolving', async () => {
+    const filename = join(dir, 'is-a-directory');
+    mkdirSync(filename);
+    const { error, ms } = await refusalOf(make(filename));
+    expectNamedRefusal(error, filename, 'SQLITE_CANTOPEN');
+    expect(ms).toBeLessThan(WITHIN_MS);
+  });
+
+  it('CONTROL: a creatable path three levels deep is made, opened and answers', async () => {
+    const filename = join(dir, 'x', 'y', 'z', 'ds.db');
+    const driver = make(filename);
+    await driver.connect();
+    expect(existsSync(filename)).toBe(true);
+    expect(await driver.execute('SELECT 1 AS one')).toEqual([{ one: 1 }]);
+  });
+});
@@ -155,6 +155,7 @@ import {
   type UndeliveredAttribute,
 } from './builtin-column-collision.js';
 import { recoverUnencodedJsonText } from './unencoded-json-text.js';
+import { makeDatabaseDirectory, SqliteDatabaseFileError } from './sqlite-database-file.js';
 import { jsonMembershipPredicate } from '@objectstack/core';
 import knex, { Knex } from 'knex';
 import { nanoid } from 'nanoid';
@@ -7001,6 +7002,16 @@ export class SqlDriver implements IDataDriver {
       // let the step-down message that follows explain the outcome. Any OTHER
       // PRAGMA failure keeps the full warning (with stack) as before.
       const code = (e as { code?: string } | null | undefined)?.code;
+      // The file itself cannot be opened or created (#23696): a directory that
+      // exists but refuses the file, a path SQLite cannot open. Every later
+      // statement would answer the same, so the connect fails here, naming the
+      // file — before, it logged and resolved, and the datasource counted as
+      // connected while it could not answer one query.
+      if (code === 'SQLITE_CANTOPEN') {
+        const declared = (this.config as any).connection;
+        const filename = this.sqliteFilename() ?? String(typeof declared === 'string' ? declared : declared?.filename);
+        throw new SqliteDatabaseFileError(filename, 'cannot be opened or created', e);
+      }
       const msg = e instanceof Error ? e.message : String(e);
       const isNativeLoadFailure =
         code === 'ERR_DLOPEN_FAILED' ||
@@ -20105,15 +20116,20 @@ export class SqlDriver implements IDataDriver {
 
   protected async ensureDatabaseExists() {
     // SQLite auto-creates database files but NOT parent directories.
-    // Ensure the directory exists so better-sqlite3 can create the file.
+    // Ensure the directory exists so better-sqlite3 can create the file — with
+    // a bounded walk, never Node's recursive mkdir, which loops forever on a
+    // path like `/proc/x/` (#23696, see `makeDatabaseDirectory`).
     if (this.isSqlite) {
       const filename = this.sqliteFilename();
       if (filename) {
         const { dirname } = await import('node:path');
-        const { mkdir } = await import('node:fs/promises');
         const dir = dirname(filename);
         if (dir && dir !== '.') {
-          await mkdir(dir, { recursive: true });
+          try {
+            await makeDatabaseDirectory(dir);
+          } catch (e) {
+            throw new SqliteDatabaseFileError(filename, `cannot be created: its directory '${dir}' could not be made`, e);
+          }
         }
       }
       return;
 
@@ -0,0 +1,77 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+
+import { mkdir, stat } from 'node:fs/promises';
+import { dirname, isAbsolute, resolve } from 'node:path';
+
+/**
+ * A SQLite database file this driver cannot open or create (#23696).
+ *
+ * Thrown by `SqlDriver.connect()`, so the boot's connect refusal (ADR-0062 D5,
+ * `datasource '<name>': connect failed — <reason>`) carries the path and the
+ * operating system's own answer instead of waiting for a plugin start timeout.
+ * `code` is the underlying error's (`ENOENT`, `EACCES`, `ENOTDIR`,
+ * `SQLITE_CANTOPEN`, …) and `cause` the error itself.
+ */
+export class SqliteDatabaseFileError extends Error {
+  readonly code: string | undefined;
+  readonly filename: string;
+  /** The error the operating system or SQLite answered. */
+  readonly cause: unknown;
+
+  constructor(filename: string, detail: string, cause: unknown) {
+    const reason = cause instanceof Error ? cause.message : String(cause);
+    const code = (cause as { code?: unknown } | null | undefined)?.code;
+    const where = isAbsolute(filename) ? `'${filename}'` : `'${filename}' (resolved: '${resolve(filename)}')`;
+    super(`SQLite database file ${where} ${detail}: ${reason}`);
+    this.name = 'SqliteDatabaseFileError';
+    this.code = typeof code === 'string' ? code : undefined;
+    this.filename = filename;
+    this.cause = cause;
+  }
+}
+
+/**
+ * Make `dir` exist, creating each missing level with a NON-recursive `mkdir`,
+ * and reject at once with the first level the operating system refuses.
+ *
+ * ## Why not `mkdir(dir, { recursive: true })`
+ *
+ * Node's recursive mkdir (v22.22.0, measured; sync and async alike) never
+ * settles when a level answers `ENOENT` although its parent exists. On
+ * `/proc/os-23696` it loops `mkdir("/proc/os-23696") = ENOENT`,
+ * `mkdir("/proc") = EEXIST`, `statx("/proc")` (a directory, so retry the
+ * child) without end — about 1,640 failing `mkdir` calls a second, all of
+ * it system CPU. A declared SQLite datasource whose directory lay on such a
+ * path never finished its connect, and the boot was refused only by a plugin
+ * start timeout that named neither the datasource nor the path.
+ *
+ * The walk below is bounded by the path's depth: find the nearest level that
+ * exists, then create the missing ones top-down. `EEXIST` on a level is a
+ * concurrent creator winning the race and is accepted; any other refusal is
+ * the answer. When a file holds the nearest existing name, the operating
+ * system answers for it too: `ENOTDIR` from the first missing level under it,
+ * or `EEXIST` from asking for `dir` itself.
+ */
+export async function makeDatabaseDirectory(dir: string): Promise<void> {
+  const missing: string[] = [];
+  let level = resolve(dir);
+  for (;;) {
+    try {
+      if (!(await stat(level)).isDirectory() && missing.length === 0) await mkdir(level);
+      break;
+    } catch (e) {
+      if ((e as { code?: unknown } | null)?.code !== 'ENOENT') throw e;
+      missing.push(level);
+      const parent = dirname(level);
+      if (parent === level) break;
+      level = parent;
+    }
+  }
+  for (const each of missing.reverse()) {
+    try {
+      await mkdir(each);
+    } catch (e) {
+      if ((e as { code?: unknown } | null)?.code !== 'EEXIST') throw e;
+    }
+  }
+}