diff --git a/projects/proj4/build.sh b/projects/proj4/build.sh
index a60e82436..1e0af1d1d 100755
--- a/projects/proj4/build.sh
+++ b/projects/proj4/build.sh
@@ -18,7 +18,7 @@
 ./autogen.sh
 ./configure
 make clean -s
-make -j$(nproc) -s
+(cd src && make -j$(nproc) -s)
 
 ./test/fuzzers/build_google_oss_fuzzers.sh
 ./test/fuzzers/build_seed_corpus.sh