diff --git a/.github/scripts/defaults.sh b/.github/scripts/defaults.sh
index e6671996..f1a27049 100755
--- a/.github/scripts/defaults.sh
+++ b/.github/scripts/defaults.sh
@@ -44,7 +44,7 @@ mapping["chipyard-digitaltop"]=" TOP=DigitalTop"
 mapping["chipyard-streaming-fir"]=" CONFIG=StreamingFIRRocketConfig"
 mapping["chipyard-streaming-passthrough"]=" CONFIG=StreamingPassthroughRocketConfig"
 mapping["chipyard-hetero"]=" CONFIG=LargeBoomAndRocketConfig"
-mapping["chipyard-boom"]=" CONFIG=SmallBoomConfig"
+mapping["chipyard-boom"]=" CONFIG=MediumBoomCosimConfig"
 mapping["chipyard-spike"]=" CONFIG=SpikeConfig"
 mapping["chipyard-blkdev"]=" CONFIG=SimBlockDeviceRocketConfig"
 mapping["chipyard-hwacha"]=" CONFIG=HwachaRocketConfig"