diff --git a/cmd/scheme.gpr.in b/cmd/scheme.gpr.in
index 0576875..2b15676 100644
--- a/cmd/scheme.gpr.in
+++ b/cmd/scheme.gpr.in
@@ -26,7 +26,8 @@ project Scheme is
 	package Compiler is
 		for Default_Switches ("Ada") use (
 			"-gnata", "-gnato", "-gnatN",  "-gnatwl", "-gnat95", "-gnatW8", "-g",
-			"-I@abs_srcdir@/../lib"
+			"-I@abs_srcdir@/../lib",
+			"-I@abs_srcdir@/../lib/posix"
 		);
 	end Compiler;
 
diff --git a/lib/lib.gpr.in b/lib/lib.gpr.in
index 72c0845..1cdbcbf 100644
--- a/lib/lib.gpr.in
+++ b/lib/lib.gpr.in
@@ -1,6 +1,9 @@
 project Lib is
 
-	for Source_Dirs use ("@abs_srcdir@");
+	for Source_Dirs use (
+		"@abs_srcdir@",
+		"@abs_srcdir@/posix"
+	);
 	for Library_Name use "h2";
 	for Library_Kind use "dynamic";
 	for Library_Dir use ".";
@@ -20,9 +23,13 @@ project Lib is
 		"h2-scheme-execute-evaluate.adb",
 		"h2-scheme-token.adb",
 		"h2-slim.ads",
+		"h2-sysapi.adb",
+		"h2-sysapi.ads",
+		"h2-sysapi-file.adb",
 		"h2-utf8.adb",
 		"h2-utf8.ads",
-		"h2-wide.ads"
+		"h2-wide.ads",
+		"h2-wide_wide.ads"
 	);
 	for Library_Interface use (
 		"h2",
@@ -30,8 +37,10 @@ project Lib is
 		"h2.pool",
 		"h2.scheme",
 		"h2.slim",
+		"h2.sysapi",
 		"h2.utf8",
-		"h2.wide"
+		"h2.wide",
+		"h2.wide_wide"
 	);
 
 	package Compiler is