diff --git a/.github/workflows/c-cpp.yml b/.github/workflows/c-cpp.yml
index ea86c9e..735a15b 100644
--- a/.github/workflows/c-cpp.yml
+++ b/.github/workflows/c-cpp.yml
@@ -13,7 +13,7 @@ jobs:
 
     steps:
     - name: Install packages
-      run: sudo apt-get -y install libbsd-dev
+      run: sudo apt-get -y install libbsd-dev pkgconf
     - name: Checkout sources
       uses: actions/checkout@v3
     - name: Make build
diff --git a/GNUmakefile b/GNUmakefile
index 206342f..050f78f 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -1,8 +1,6 @@
-CFLAGS=		-D_DEFAULT_SOURCE -D_GNU_SOURCE \
-		-DLIBBSD_OVERLAY -isystem /usr/include/bsd \
-		-isystem /usr/local/include/bsd \
-		-Wall
-LDFLAGS=	-lbsd
+CFLAGS+=	-D_DEFAULT_SOURCE -D_GNU_SOURCE -Wall \
+		$(shell pkgconf --cflags libbsd-overlay)
+LDFLAGS+=	$(shell pkgconf --libs libbsd-overlay)
 BINDIR?=        /usr/local/bin
 MANDIR?=        /usr/local/man/man