diff --git a/.github/scripts/build.sh b/.github/scripts/build.sh
index 861f30b83..f74f2f646 100755
--- a/.github/scripts/build.sh
+++ b/.github/scripts/build.sh
@@ -19,6 +19,7 @@ export TEST_NETWORK=${NETWORK:-"regtest"}
 export TIMEOUT=900
 export VALGRIND=${VALGRIND:-0}
 export FUZZING=${FUZZING:-0}
+export LIGHTNINGD_POSTGRES_NO_VACUUM=1
 
 pip3 install --user -U \
      -r requirements.lock
diff --git a/wallet/db_postgres.c b/wallet/db_postgres.c
index 29920a358..973097fe1 100644
--- a/wallet/db_postgres.c
+++ b/wallet/db_postgres.c
@@ -254,6 +254,14 @@ static void db_postgres_teardown(struct db *db)
 static bool db_postgres_vacuum(struct db *db)
 {
 	PGresult *res;
+
+#if DEVELOPER
+	/* This can use a lot of diskspacem breaking CI! */
+	if (getenv("LIGHTNINGD_POSTGRES_NO_VACUUM")
+	    && streq(getenv("LIGHTNINGD_POSTGRES_NO_VACUUM"), "1"))
+		return true;
+#endif
+
 	res = PQexec(db->conn, "VACUUM FULL;");
 	if (PQresultStatus(res) != PGRES_COMMAND_OK) {
 		db->error = tal_fmt(db, "BEGIN command failed: %s",