diff --git a/TODO b/TODO
index dd4cd66..5291dea 100644
--- a/TODO
+++ b/TODO
@@ -79,3 +79,22 @@ Description: move the unit test suites to a unit/ subdirectory so that
              integration tests and benchmarks can be cleanly separated
 
 ---
+
+ID: 4
+Type: feature
+Title: implement Rabin-Karp rolling hash algorithm
+Status: open
+Priority: high
+Created: 2025-05-05
+Description: After testing a couple of string search algorithms, I've ditched
+             the idea of using KMP as my use-case gives no advantage compared to
+             naive searching. In addition I've came upon the challenge that many
+             string search algorithms are optimized for search on a linear
+             buffer, which in my case is not applicable as the implementation
+             the search algorithm is for uses a circular buffer. Rabin-Karp
+             seemed promising. I've come up with a different approach though,
+             which is still based on rolling hashes, therefore, as a base, I
+             need an implementation of the original Rabin-Karp rolling hash
+             algorithm
+
+---