update readme

Author: marcincuber

README.md

@@ -37,6 +37,10 @@ You will find configurations for:
 
 Check out my stories on medium if you interested in finding out more on specific topics.
 
+### Amazon EKS upgrade 1.28 to 1.29
+
+[Amazon EKS upgrade journey from 1.28 to 1.29](https://marcincuber.medium.com/amazon-eks-upgrade-journey-from-1-28-to-1-29-say-hello-to-mandala-858ae0579f4f)
+
 ### Amazon EKS upgrade 1.27 to 1.28
 
 [Amazon EKS upgrade journey from 1.27 to 1.28](https://marcincuber.medium.com/amazon-eks-upgrade-journey-from-1-27-to-1-28-welcoming-planternetes-44985e11463a)