diff --git a/gnu/packages/axoloti.scm b/gnu/packages/axoloti.scm
index 2f8497e3ddf..a36210b7d41 100644
--- a/gnu/packages/axoloti.scm
+++ b/gnu/packages/axoloti.scm
@@ -315,6 +315,8 @@ runtime.")
                                                                  "share/axoloti"))
                               (toolchain (assoc-ref inputs "cross-toolchain"))
                               (includes  (string-append
+                                          toolchain
+                                          "/arm-none-eabi/include/:"
                                           toolchain
                                           "/arm-none-eabi/include/c++:"
                                           toolchain