diff --git a/src/vcfpp.h b/inst/include/vcfpp.h
similarity index 100%
rename from src/vcfpp.h
rename to inst/include/vcfpp.h
diff --git a/src/Makevars b/src/Makevars
index 9735e18..de596aa 100644
--- a/src/Makevars
+++ b/src/Makevars
@@ -1,6 +1,6 @@
 HTSLIB_DIR='htslib-1.19.1'
-PKG_CPPFLAGS=-I. -I${HTSLIB_DIR}
-PKG_LIBS=${HTSLIB_DIR}/libhts.a -fPIC -lz -lm -lbz2 -llzma -lcurl
+PKG_CPPFLAGS = -I${HTSLIB_DIR} -I../inst/include
+PKG_LIBS = ${HTSLIB_DIR}/libhts.a -fPIC -lz -lm -lbz2 -llzma -lcurl
 
 .PHONY: all clean HTSLIB
 
diff --git a/src/Makevars.win b/src/Makevars.win
index 2a4f6c9..d96f485 100644
--- a/src/Makevars.win
+++ b/src/Makevars.win
@@ -1,5 +1,5 @@
 HTSLIB_DIR=htslib-1.18
-PKG_CPPFLAGS=-I. -I${HTSLIB_DIR} -D_FILE_OFFSET_BITS=64
+PKG_CPPFLAGS = -I${HTSLIB_DIR} -I../inst/include -D_FILE_OFFSET_BITS=64
 PKG_LIBS=${HTSLIB_DIR}/libhts.a
 
 ifeq (,$(shell pkg-config --version 2>/dev/null))