diff --git a/eval/runner/adapters/hybrid-nograph.ts b/eval/runner/adapters/hybrid-nograph.ts
index 5c99a36e7..be5cde0eb 100644
--- a/eval/runner/adapters/hybrid-nograph.ts
+++ b/eval/runner/adapters/hybrid-nograph.ts
@@ -76,6 +76,11 @@ export class HybridNoGraphAdapter implements Adapter {
     return { engine } satisfies HybridNoGraphState;
   }
 
+  async teardown(state: BrainState): Promise<void> {
+    const s = state as HybridNoGraphState;
+    await s.engine.disconnect();
+  }
+
   /** Build a markdown string importFromContent can parse.
    *  Format: YAML frontmatter then body; matches what gbrain import expects. */
   private buildContentMarkdown(p: Page): string {
diff --git a/eval/runner/multi-adapter.ts b/eval/runner/multi-adapter.ts
index 8247614ee..4aa4782c3 100644
--- a/eval/runner/multi-adapter.ts
+++ b/eval/runner/multi-adapter.ts
@@ -217,6 +217,11 @@ class GbrainAfterAdapter implements Adapter {
       rank: i + 1,
     }));
   }
+
+  async teardown(state: unknown): Promise<void> {
+    const { engine } = state as { engine: PGLiteEngine };
+    await engine.disconnect();
+  }
 }
 
 /**
@@ -340,6 +345,7 @@ async function scoreOneRun(
     for (const r of topK) if (relevant.has(r.page_id)) totalCorrect++;
     totalExpected += relevant.size;
   }
+  if (adapter.teardown) await adapter.teardown(state);
   return {
     mean_precision_at_k: queries.length > 0 ? totalP / queries.length : 0,
     mean_recall_at_k: queries.length > 0 ? totalR / queries.length : 0,
diff --git a/eval/runner/types.ts b/eval/runner/types.ts
index af53fc81c..36a3694d2 100644
--- a/eval/runner/types.ts
+++ b/eval/runner/types.ts
@@ -179,6 +179,14 @@ export interface Adapter {
    * Adapters that don't have a poison path return an empty map.
    */
   getPoisonDisposition?(state: BrainState): Record<string, PoisonDisposition>;
+
+  /**
+   * Release any resources held by `state` (DB connections, file locks,
+   * worker threads). Called once per run after scoring completes.
+   * Adapters that hold no resources can omit this. Without it, PGLite-backed
+   * adapters leak engine workers and Bun exits 99 at the end of the run.
+   */
+  teardown?(state: BrainState): Promise<void>;
 }
 
 // ─── Scorer helpers ─────────────────────────────────────────────────