diff --git a/aider_gitea/__main__.py b/aider_gitea/__main__.py
index 3d1b6ac..304f29c 100644
--- a/aider_gitea/__main__.py
+++ b/aider_gitea/__main__.py
@@ -15,8 +15,8 @@ import subprocess
 import os
 
 import re
-
 from . import secrets
+from .seen_issues_db import SeenIssuesDB
 
 def generate_branch_name(issue_number: str, issue_title: str) -> str:
     """
@@ -134,6 +134,7 @@ def main():
     logging.basicConfig(level='INFO')
     args = parse_args()
 
+    seen_issues_db = SeenIssuesDB()
     client = GiteaClient(args.gitea_url, secrets.gitea_token())
 
     try:
@@ -150,7 +151,13 @@ def main():
         issue_number = issue.get("number")
         issue_description = issue.get("body", "")
         title = issue.get("title", f"Issue {issue_number}")
+        issue_text = f"{title}\n{issue_description}"
+        if seen_issues_db.has_seen(issue_text):
+            logger.info(f"Skipping already processed issue #{issue_number}: {title}")
+            continue
+
         branch_name = generate_branch_name(issue_number, title)
+        seen_issues_db.mark_as_seen(issue_text)
         try:
             with tempfile.TemporaryDirectory() as tmpdirname:
                 process_issue(args, Path(tmpdirname), branch_name, title, issue_description, issue_number)
diff --git a/aider_gitea/seen_issues_db.py b/aider_gitea/seen_issues_db.py
new file mode 100644
index 0000000..7fb8ea7
--- /dev/null
+++ b/aider_gitea/seen_issues_db.py
@@ -0,0 +1,28 @@
+import sqlite3
+from hashlib import sha256
+
+class SeenIssuesDB:
+    def __init__(self, db_path='seen_issues.db'):
+        self.conn = sqlite3.connect(db_path)
+        self._create_table()
+
+    def _create_table(self):
+        with self.conn:
+            self.conn.execute('''
+                CREATE TABLE IF NOT EXISTS seen_issues (
+                    issue_hash TEXT PRIMARY KEY
+                )
+            ''')
+
+    def mark_as_seen(self, issue_text: str):
+        issue_hash = self._compute_hash(issue_text)
+        with self.conn:
+            self.conn.execute('INSERT OR IGNORE INTO seen_issues (issue_hash) VALUES (?)', (issue_hash,))
+
+    def has_seen(self, issue_text: str) -> bool:
+        issue_hash = self._compute_hash(issue_text)
+        cursor = self.conn.execute('SELECT 1 FROM seen_issues WHERE issue_hash = ?', (issue_hash,))
+        return cursor.fetchone() is not None
+
+    def _compute_hash(self, text: str) -> str:
+        return sha256(text.encode('utf-8')).hexdigest()
diff --git a/test/test_seen_issues_db.py b/test/test_seen_issues_db.py
new file mode 100644
index 0000000..7d13d4e
--- /dev/null
+++ b/test/test_seen_issues_db.py
@@ -0,0 +1,25 @@
+import sys
+import unittest
+from pathlib import Path
+
+# Add the aider_gitea module to the Python path
+sys.path.append(str(Path(__file__).resolve().parent.parent))
+from aider_gitea.seen_issues_db import SeenIssuesDB
+
+class TestSeenIssuesDB(unittest.TestCase):
+
+    def setUp(self):
+        self.db = SeenIssuesDB(':memory:')
+
+    def test_mark_and_check_seen_issue(self):
+        issue_text = "Test issue"
+        self.assertFalse(self.db.has_seen(issue_text))
+        self.db.mark_as_seen(issue_text)
+        self.assertTrue(self.db.has_seen(issue_text))
+
+    def test_unseen_issue(self):
+        issue_text = "Unseen issue"
+        self.assertFalse(self.db.has_seen(issue_text))
+
+if __name__ == '__main__':
+    unittest.main()