diff --git a/.gitignore b/.gitignore
index 78cdbb5..aeae0d6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -34,6 +34,7 @@
 # Custom
 
 /Makefile.in
+/include/Makefile.in
 
 ###########################################
 # Only generated when configuring in root #
@@ -51,5 +52,6 @@
 # Custom
 
 /Makefile
+/include/Makefile
 
 /autotools-project
diff --git a/Makefile.am b/Makefile.am
index 325fd95..d9a0fcb 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,3 +1,5 @@
+SUBDIRS = include
+
 AM_CFLAGS = \
 	-std=c99 \
 	-pedantic \
@@ -7,6 +9,10 @@ AM_CFLAGS = \
 	-I$(top_srcdir)/include
 
 bin_PROGRAMS = autotools-project
+lib_LIBRARIES = libautotools-project.a
 
 autotools_project_SOURCES = \
 	src/main.c
+
+libautotools_project_a_SOURCES = \
+	src/lib.c
diff --git a/README.md b/README.md
index 8393736..78a80c7 100644
--- a/README.md
+++ b/README.md
@@ -12,4 +12,4 @@ Don't forget to change the following files:
 * `Makefile.am`
 * `README.md`
 
-Remove submodule `vendor/cross` if you don't need it.
+Remove directory `include` and submodule `vendor/cross` if you don't need them.
diff --git a/configure.ac b/configure.ac
index 42b9e76..80f6b02 100644
--- a/configure.ac
+++ b/configure.ac
@@ -17,6 +17,7 @@ AM_INIT_AUTOMAKE([1.9 subdir-objects])
 
 AC_CONFIG_FILES([
   Makefile
+  include/Makefile
 ])
 
 AC_LANG([C])
diff --git a/include/Makefile.am b/include/Makefile.am
new file mode 100644
index 0000000..3a495c4
--- /dev/null
+++ b/include/Makefile.am
@@ -0,0 +1,2 @@
+nobase_include_HEADERS = \
+	autotools-project.h
diff --git a/include/autotools-project.h b/include/autotools-project.h
new file mode 100644
index 0000000..f43ed77
--- /dev/null
+++ b/include/autotools-project.h
@@ -0,0 +1,14 @@
+#ifndef _AUTOTOOLS_PROJECT_H
+#define _AUTOTOOLS_PROJECT_H 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int autotools_project(int a, int b);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/src/lib.c b/src/lib.c
new file mode 100644
index 0000000..670dda6
--- /dev/null
+++ b/src/lib.c
@@ -0,0 +1,10 @@
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <autotools-project.h>
+
+int autotools_project(const int a, const int b)
+{
+    return a + b;
+}
diff --git a/src/main.c b/src/main.c
index de1e707..9f21cbd 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,3 +1,7 @@
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
 int main(const int argc __attribute__((unused)), char **const argv __attribute__((unused)))
 {
     return 0;