diff --git a/src/lib/server/backends/schema.ts b/src/lib/server/backends/schema.ts
index 506debf..0736c54 100644
--- a/src/lib/server/backends/schema.ts
+++ b/src/lib/server/backends/schema.ts
@@ -41,6 +41,7 @@ export function migrateNativeInstances(handle: Database.Database): void {
             creation_id TEXT PRIMARY KEY REFERENCES server_deployments(id),
             cleanup_id TEXT NOT NULL UNIQUE REFERENCES server_deployments(id)
         );
+        CREATE INDEX IF NOT EXISTS idx_ec_host_migrations_instance ON ec_host_migrations(instance_id);
     `);
 }
 
diff --git a/src/lib/server/db/index.ts b/src/lib/server/db/index.ts
index 8796ff8..ed039cc 100644
--- a/src/lib/server/db/index.ts
+++ b/src/lib/server/db/index.ts
@@ -10,6 +10,7 @@ import { backfillLeaderboard } from '../fleet/leaderboard-ingest.js';
 import { initializeFleetSettings } from './fleet-settings.js';
 import { migrateServerHistory } from './server-history.js';
 import { migrateNativeInstances } from '../backends/schema.js';
+import { installPerformanceIndexes } from './performance-indexes.js';
 import { timeStatement } from './slow-statements.js';
 
 let _db: Database.Database | null = null;
@@ -404,6 +405,7 @@ export function db(): Database.Database {
             ON server_deployments(finished_at) WHERE server_deleted_at IS NULL;
             CREATE INDEX IF NOT EXISTS idx_server_deployments_unsettled
             ON server_deployments(id) WHERE state NOT IN ('done','warning','cancelled');`);
+        installPerformanceIndexes(handle);
         installReportRevisions(handle);
     } catch (err) {
         handle.close();
diff --git a/src/lib/server/db/performance-indexes.ts b/src/lib/server/db/performance-indexes.ts
new file mode 100644
index 0000000..6fad551
--- /dev/null
+++ b/src/lib/server/db/performance-indexes.ts
@@ -0,0 +1,27 @@
+import type Database from 'better-sqlite3';
+
+/** Install after additive column and history migrations, on new and existing databases. */
+export function installPerformanceIndexes(handle: Database.Database): void {
+    handle.exec(`
+        CREATE INDEX IF NOT EXISTS idx_staged_files_deployment_file ON staged_file_changes(deployment_file_id);
+        CREATE INDEX IF NOT EXISTS idx_beta_test_runs_beta_revision ON beta_test_runs(beta_id, revision);
+        CREATE INDEX IF NOT EXISTS idx_deployments_beta ON deployments(beta_id);
+        CREATE INDEX IF NOT EXISTS idx_deployments_script ON deployments(script_id);
+        CREATE INDEX IF NOT EXISTS idx_deployments_version ON deployments(script_version_id);
+        CREATE INDEX IF NOT EXISTS idx_deployments_prior ON deployments(prior_version_id);
+        CREATE INDEX IF NOT EXISTS idx_deployment_scripts_script ON deployment_scripts(script_id);
+        CREATE INDEX IF NOT EXISTS idx_deployment_scripts_version ON deployment_scripts(script_version_id);
+        CREATE INDEX IF NOT EXISTS idx_deployment_scripts_prior ON deployment_scripts(prior_version_id);
+        CREATE INDEX IF NOT EXISTS idx_server_scripts_version ON server_scripts(script_version_id);
+        CREATE INDEX IF NOT EXISTS idx_betas_version ON betas(script_version_id);
+        CREATE INDEX IF NOT EXISTS idx_beta_scripts_version ON beta_scripts(script_version_id);
+        CREATE INDEX IF NOT EXISTS idx_beta_servers_prior ON beta_servers(prior_version_id);
+        CREATE INDEX IF NOT EXISTS idx_beta_server_scripts_script ON beta_server_scripts(script_id);
+        CREATE INDEX IF NOT EXISTS idx_beta_server_scripts_prior ON beta_server_scripts(prior_version_id);
+        CREATE INDEX IF NOT EXISTS idx_beta_file_snapshots_server ON beta_file_snapshots(server);
+        CREATE INDEX IF NOT EXISTS idx_server_launch_previews_deployment ON server_launch_previews(deployment_id);
+        CREATE INDEX IF NOT EXISTS idx_server_collection_previews_collection ON server_collection_previews(collection_id);
+        CREATE INDEX IF NOT EXISTS idx_server_collection_removals_deployment ON server_collection_removals(deployment_id);
+        CREATE INDEX IF NOT EXISTS idx_server_creation_dependencies_removal ON server_creation_dependencies(removal_id);
+    `);
+}
diff --git a/src/lib/server/game-files/schema.ts b/src/lib/server/game-files/schema.ts
index 12146d7..20086c0 100644
--- a/src/lib/server/game-files/schema.ts
+++ b/src/lib/server/game-files/schema.ts
@@ -48,6 +48,7 @@ export function ensureGameFileSchema(handle: Database.Database): void {
             FROM game_file_versions v,json_each(v.manifest) f;
         CREATE TRIGGER IF NOT EXISTS game_file_versions_immutable BEFORE UPDATE ON game_file_versions
         WHEN OLD.state = 'ready' BEGIN SELECT RAISE(ABORT, 'Published game-file versions are immutable'); END;
+        CREATE INDEX IF NOT EXISTS idx_host_library_caches_version ON host_library_caches(version_id);
     `);
     const versionColumns = handle.prepare('PRAGMA table_info(game_file_versions)').all() as { name: string }[];
     if (!versionColumns.some(column => column.name === 'last_activity_at')) handle.exec('ALTER TABLE game_file_versions ADD COLUMN last_activity_at TEXT');
diff --git a/src/lib/server/hosts/schema.ts b/src/lib/server/hosts/schema.ts
index 37ec541..d46f89e 100644
--- a/src/lib/server/hosts/schema.ts
+++ b/src/lib/server/hosts/schema.ts
@@ -89,6 +89,8 @@ export function ensureHostSchema(handle: Database.Database): void {
                 CHECK(stage IN ('queued','running','cleaned','failed','completed')),
             requested_at TEXT NOT NULL, updated_at TEXT NOT NULL, cleaned_at TEXT, error TEXT
         );
+        CREATE INDEX IF NOT EXISTS idx_ec_host_credentials_host ON ec_host_credentials(host_id);
+        CREATE INDEX IF NOT EXISTS idx_ec_host_enrollments_host ON ec_host_enrollments(host_id);
     `);
     const columns = handle.prepare('PRAGMA table_info(ec_host_operations)').all() as { name: string }[];
     if (!columns.some(column => column.name === 'history_expired_at')) handle.exec('ALTER TABLE ec_host_operations ADD COLUMN history_expired_at TEXT');
diff --git a/tests/unit/database-indexes.test.ts b/tests/unit/database-indexes.test.ts
new file mode 100644
index 0000000..0996606
--- /dev/null
+++ b/tests/unit/database-indexes.test.ts
@@ -0,0 +1,44 @@
+import { afterEach, beforeEach, expect, it, vi } from 'vitest';
+import { newFixture, type Fixture } from '../helpers/fixture.js';
+
+let fixture: Fixture;
+beforeEach(async () => { vi.resetModules(); fixture = await newFixture([]); });
+afterEach(async () => { await fixture.cleanup(); });
+
+it('indexes campaign cascades and beta evidence on fresh and reopened databases', async () => {
+    const { db, closeDb } = await import('../../src/lib/server/db/index.js');
+    for (let pass = 0; pass < 2; pass++) {
+        const handle = db();
+        for (const [query, index] of [
+            ['SELECT id FROM staged_file_changes WHERE deployment_file_id = 1', 'idx_staged_files_deployment_file'],
+            ['SELECT id FROM beta_test_runs WHERE beta_id = 1 AND revision = 2', 'idx_beta_test_runs_beta_revision']
+        ]) {
+            const plan = handle.prepare(`EXPLAIN QUERY PLAN ${query}`).all() as { detail: string }[];
+            expect(plan.some(row => row.detail.includes(index))).toBe(true);
+        }
+        expect(handle.pragma('foreign_key_check')).toEqual([]);
+        closeDb();
+    }
+});
+
+it('covers every foreign key child prefix, including lazy host and library schemas', async () => {
+    const { db } = await import('../../src/lib/server/db/index.js');
+    const { ensureHostSchema } = await import('../../src/lib/server/hosts/schema.js');
+    const { ensureGameFileSchema } = await import('../../src/lib/server/game-files/schema.js');
+    const handle = db();
+    ensureHostSchema(handle); ensureGameFileSchema(handle);
+    const tables = handle.prepare("SELECT name FROM sqlite_master WHERE type='table'").all() as { name: string }[];
+    const missing: string[] = [];
+    for (const { name } of tables) {
+        const foreignKeys = handle.pragma(`foreign_key_list(${name})`) as { from: string; seq: number }[];
+        const indexes = handle.pragma(`index_list(${name})`) as { name: string; partial: number }[];
+        const prefixes = indexes.filter(index => !index.partial).map(index =>
+            (handle.pragma(`index_info(${index.name})`) as { name: string }[])[0]?.name);
+        const columns = handle.pragma(`table_info(${name})`) as { name: string; type: string; pk: number }[];
+        if (columns.filter(column => column.pk).length === 1) prefixes.push(columns.find(column => column.pk)?.name);
+        for (const key of foreignKeys.filter(key => key.seq === 0)) {
+            if (!prefixes.includes(key.from)) missing.push(`${name}.${key.from}`);
+        }
+    }
+    expect(missing).toEqual([]);
+});