diff --git a/.github/codecov.yml b/.github/codecov.yml
index 5d1f8d64b7..8c5c4bf62b 100644
--- a/.github/codecov.yml
+++ b/.github/codecov.yml
@@ -9,3 +9,5 @@ flags:
     carryforward: true
   ledgers:
     carryforward: true
+  nightly_ledgers:
+    carryforward: true
diff --git a/src/flamenco/runtime/tests/run_ledger_tests.sh b/src/flamenco/runtime/tests/run_ledger_tests.sh
index 366c37a1cd..1b595f6be2 100755
--- a/src/flamenco/runtime/tests/run_ledger_tests.sh
+++ b/src/flamenco/runtime/tests/run_ledger_tests.sh
@@ -57,7 +57,7 @@ PROTO_BUF_FAILURE=0
 TILE_CPUS="--tile-cpus 5-21"
 
 POSITION_ARGS=()
-OBJDIR=${OBJDIR:-build/native/gcc}
+OBJDIR=${OBJDIR:-build/native/clang}
 
 while [[ $# -gt 0 ]]; do
   case $1 in
@@ -211,7 +211,7 @@ while [[ $# -gt 0 ]]; do
 done
 
 
-export LLVM_PROFILE_FILE=$OBJDIR/cov/raw/ledger_test_$LEDGER.profraw
+export LLVM_PROFILE_FILE=$OBJDIR/cov/raw/ledger_test_$$.profraw
 mkdir -p $OBJDIR/cov/raw
 
 if [[ ! -e dump/$CHECKPT && SKIP_INGEST -eq 1 ]]; then
diff --git a/src/flamenco/runtime/tests/run_nightly_tests.sh b/src/flamenco/runtime/tests/run_nightly_tests.sh
index 4c9c4d9326..5ae525f441 100755
--- a/src/flamenco/runtime/tests/run_nightly_tests.sh
+++ b/src/flamenco/runtime/tests/run_nightly_tests.sh
@@ -53,17 +53,13 @@ EOF
 curl -X POST -H 'Content-type: application/json' --data "$start_json_payload" $SLACK_WEBHOOK_URL
 
 # Set up environment
-PATH=/opt/rh/gcc-toolset-12/root/usr/bin:$PATH
-export PATH
-PKG_CONFIG_PATH=/usr/lib64/pkgconfig:$PKG_CONFIG_PATH
-
 make distclean && make clean
 ./deps.sh nuke
 echo "y" | ./deps.sh +dev
-make -j
+make -j CC=clang EXTRAS=llvm-cov
 
 # Run the test
-make run-runtime-test-nightly > ~/run_nightly_tests.txt
+make run-runtime-test-nightly -j CC=clang EXTRAS=llvm-cov > ~/run_nightly_tests.txt
 status=$?
 
 # Notify the test status