diff --git a/src/ci/run.sh b/src/ci/run.sh
index 194723eb3252e..353a8d368d54a 100755
--- a/src/ci/run.sh
+++ b/src/ci/run.sh
@@ -238,6 +238,10 @@ datecheck() {
 datecheck
 trap datecheck EXIT
 
+# Bump this value if you need to invalidate sccache's cache, if some wrong
+# builds go into it
+export SCCACHE_C_CUSTOM_CACHE_BUSTER=1
+
 # We've had problems in the past of shell scripts leaking fds into the sccache
 # server (#48192) which causes Cargo to erroneously think that a build script
 # hasn't finished yet. Try to solve that problem by starting a very long-lived