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--- a/README.md
+++ b/README.md
@@ -1,2 +1,5 @@
 # TREXIO
 TREX I/O library
+
+Note: The code should be compliant with the C99 [CERT C coding
+standard](https://resources.sei.cmu.edu/downloads/secure-coding/assets/sei-cert-c-coding-standard-2016-v01.pdf). This can be checked with the `cppcheck` tool.