diff --git a/src/core/tracing/TdSpanExporter.ts b/src/core/tracing/TdSpanExporter.ts
index 5208669..748c939 100644
--- a/src/core/tracing/TdSpanExporter.ts
+++ b/src/core/tracing/TdSpanExporter.ts
@@ -102,8 +102,14 @@ export class TdSpanExporter implements SpanExporter {
    * Export spans using all configured adapters
    */
   export(spans: ReadableSpan[], resultCallback: (result: ExportResult) => void): void {
+    this._exportAsync(spans).then(
+      () => resultCallback({ code: ExportResultCode.SUCCESS }),
+      (error) => resultCallback({ code: ExportResultCode.FAILED, error }),
+    );
+  }
+
+  private async _exportAsync(spans: ReadableSpan[]): Promise<void> {
     if (this.mode !== TuskDriftMode.RECORD) {
-      resultCallback({ code: ExportResultCode.SUCCESS });
       return;
     }
 
@@ -171,29 +177,26 @@ export class TdSpanExporter implements SpanExporter {
       `Filtered ${filteredSpansBasedOnLibraryName.length - filteredBlockedSpans.length} blocked/oversized span(s), ${filteredBlockedSpans.length} remaining`,
     );
 
-    // Transform spans to CleanSpanData
-    const cleanSpans: CleanSpanData[] = filteredBlockedSpans.map((span) =>
-      SpanTransformer.transformSpanToCleanJSON(span, this.environment),
-    );
-
-    if (this.adapters.length === 0) {
-      logger.debug("No adapters configured");
-      resultCallback({ code: ExportResultCode.SUCCESS });
-      return;
+    // Yield the event loop between chunks to avoid blocking pool callbacks, timers, and I/O.
+    const TRANSFORM_CHUNK_SIZE = 20;
+    const cleanSpans: CleanSpanData[] = [];
+    for (let i = 0; i < filteredBlockedSpans.length; i += TRANSFORM_CHUNK_SIZE) {
+      const end = Math.min(i + TRANSFORM_CHUNK_SIZE, filteredBlockedSpans.length);
+      for (let j = i; j < end; j++) {
+        cleanSpans.push(
+          SpanTransformer.transformSpanToCleanJSON(filteredBlockedSpans[j], this.environment),
+        );
+      }
+      if (end < filteredBlockedSpans.length) {
+        await new Promise<void>((resolve) => setImmediate(resolve));
+      }
     }
 
-    // Filter adapters based on mode
-
     if (this.adapters.length === 0) {
-      logger.debug(`No active adapters for mode: ${this.mode}`);
-      resultCallback({ code: ExportResultCode.SUCCESS });
       return;
     }
 
-    // Export to all active adapters
-    Promise.all(this.adapters.map((adapter) => adapter.exportSpans(cleanSpans)))
-      .then(() => resultCallback({ code: ExportResultCode.SUCCESS }))
-      .catch((error) => resultCallback({ code: ExportResultCode.FAILED, error }));
+    await Promise.all(this.adapters.map((adapter) => adapter.exportSpans(cleanSpans)));
   }
 
   /**
diff --git a/src/core/tracing/adapters/FilesystemSpanAdapter.ts b/src/core/tracing/adapters/FilesystemSpanAdapter.ts
index d282e94..1f802bb 100644
--- a/src/core/tracing/adapters/FilesystemSpanAdapter.ts
+++ b/src/core/tracing/adapters/FilesystemSpanAdapter.ts
@@ -1,4 +1,5 @@
 import * as fs from "fs";
+import * as fsp from "fs/promises";
 import * as path from "path";
 import { ExportResult, ExportResultCode } from "@opentelemetry/core";
 import type { SpanExportAdapter } from "../TdSpanExporter";
@@ -30,22 +31,33 @@ export class FilesystemSpanAdapter implements SpanExportAdapter {
 
   async exportSpans(spans: CleanSpanData[]): Promise<ExportResult> {
     try {
+      // Group spans by trace file so we do one write per file instead of one per span.
+      const linesByFile = new Map<string, string[]>();
+
       for (const span of spans) {
         const traceId = span.traceId;
 
-        // Get or create file path for this trace ID
         let filePath = this.traceFileMap.get(traceId);
-
         if (!filePath) {
           const isoTimestamp = new Date().toISOString().replace(/[:.]/g, "-");
           filePath = path.join(this.baseDirectory, `${isoTimestamp}_trace_${traceId}.jsonl`);
           this.traceFileMap.set(traceId, filePath);
         }
 
-        const jsonLine = JSON.stringify({ ...span, kind: mapOtToPb(span.kind as OtSpanKind) }) + "\n";
-        fs.appendFileSync(filePath, jsonLine, "utf8");
+        let lines = linesByFile.get(filePath);
+        if (!lines) {
+          lines = [];
+          linesByFile.set(filePath, lines);
+        }
+        lines.push(JSON.stringify({ ...span, kind: mapOtToPb(span.kind as OtSpanKind) }));
       }
 
+      await Promise.all(
+        Array.from(linesByFile.entries()).map(([filePath, lines]) =>
+          fsp.appendFile(filePath, lines.join("\n") + "\n", "utf8"),
+        ),
+      );
+
       logger.debug(
         `Exported ${spans.length} span(s) to trace-specific files in ${this.baseDirectory}`,
       );