diff --git a/project.janet b/project.janet
index 3a1366e..692a48d 100644
--- a/project.janet
+++ b/project.janet
@@ -1,12 +1,33 @@
-(declare-project :name "geom")
+(declare-project :name "geom"
+   :dependencies ["https://github.com/joy-framework/tester"])
 
-(os/shell (string/join [
-    "mkdir" "-p" "lib2geom/build" "&&"
-    "cd" "lib2geom/build" "&&"
-    "cmake" ".." "-D2GEOM_BUILD_SHARED:BOOL=ON" "&&"
-    "make" "2geom"] " "))
+(def- is-win (= (os/which) :windows))
+(def- sep (if is-win "\\" "/"))
+(def- modext (if is-win ".dll" ".so"))
+(def- statext (if is-win ".static.lib" ".a"))
+
+(rule "lib2geom.a" []
+  (def olddir (os/cwd))
+  (try
+    (do
+      (shell "pwd")
+      (os/mkdir "lib2geom/build")
+      (os/cd "lib2geom/build")
+      (shell "cmake" ".." "-DCMAKE_CXX_FLAGS:STRING=-fPIC")
+      (shell "make" "2geom"))
+    ([err] (print "Error compiling lib2geom.a: " err)))
+  (os/cd olddir))
+(add-body "clean"
+  (shell "rm" "-rf" "lib2geom/build")
+  (print "Deleted lib2geom build directory."))
+
 (declare-native :name "geom" :source @["src/point.cpp" "src/main.cpp"]
                 :compiler "g++"
                 :linker "g++"
-                :cflags ["-Wall" "-Wextra" "-Iinclude" "-Ilib2geom/src" "-Llib2geom/build/src/2geom"]
-                :lflags ["-l2geom" "-ldl" "-ldouble-conversion" "-lgsl" "-lgslcblas" "-lm"])
+                :cflags ["-Wall" "-Wextra" "-Iinclude" "-Ilib2geom/src"]
+                :lflags ["lib2geom/build/src/2geom/lib2geom.a" "-ldl" "-ldouble-conversion" "-lgsl" "-lgslcblas" "-lm"])
+
+(def- lname (string "build" sep "geom" statext))
+(def- sname (string "build" sep "geom" modext))
+(add-dep lname "lib2geom.a")
+(add-dep sname "lib2geom.a")