diff --git a/contrib/README.md b/contrib/README.md
index 11862c2387..55e87edc4d 100644
--- a/contrib/README.md
+++ b/contrib/README.md
@@ -46,3 +46,4 @@ Git log in order to find out version and update details
 | bsps/arm/stm32h7/stm32h7xx_hal_driver | https://github.com/STMicroelectronics/stm32u5xx-hal-driver     |
 | bsps/arm/stm32u5/stm32u5xx-hal-driver | https://github.com/STMicroelectronics/stm32h7xx_hal_driver.git |
 | cpukit/fastlz                         | https://github.com/ariya/FastLZ                                |
+| cpukit/libz                           | https://github.com/madler/zlib                                 |