diff --git a/directory-tailer.ts b/directory-tailer.ts
index e577bce..24b6081 100644
--- a/directory-tailer.ts
+++ b/directory-tailer.ts
@@ -15,6 +15,8 @@ const sleep = (timeout: number) => new Promise((r) => setTimeout(r, timeout));
 export class DirectoryTailer {
   public abort = new AbortController();
 
+  lastBatchCIDs = new Set<string>();
+
   latestDate: string | undefined;
   saveRaw: boolean = true; // set to false in production so you don't double-store plc data
 
@@ -72,13 +74,19 @@ export class DirectoryTailer {
 
       let entry: ExportEntry | undefined;
       const promises = [];
+      const cids = new Set<string>();
       for (const line of new IterLines(text)) {
         entry = JSON.parse(line) as unknown as ExportEntry;
+        if (this.lastBatchCIDs.has(entry.cid)) continue;
+
         this.latestDate = entry.createdAt;
+        cids.add(entry.cid);
         promises.push(this.processRecord(entry, line));
       }
       await Promise.all(promises);
 
+      this.lastBatchCIDs = cids;
+
       if (entry) {
         this.latestDate = entry.createdAt;
         const write = Deno.writeTextFile("./data/latest-date", this.latestDate);
diff --git a/scrape.ts b/scrape.ts
index bdcb85b..59e7187 100644
--- a/scrape.ts
+++ b/scrape.ts
@@ -17,14 +17,15 @@ export const catchUp = async () => {
     lineReader.releaseLock();
   }
 
-  let lastLine: string | undefined;
+  tailer.lastBatchCIDs.clear();
   for await (const line of lineStream.values()) {
-    lastLine = line;
-  }
-
-  if (lastLine) {
-    const entry = JSON.parse(lastLine) as unknown as ExportEntry;
-    tailer.latestDate = entry.createdAt;
+    try {
+      const entry = JSON.parse(line) as unknown as ExportEntry;
+      tailer.latestDate = entry.createdAt;
+      tailer.lastBatchCIDs.add(entry.cid);
+    } catch (_err) {
+      // ignore
+    }
   }
 };