diff --git a/.gitignore b/.gitignore
index 2cf6d7dd..2ea95f2b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,11 +1,8 @@
 obj/*
 bin/*
-*.ninja*
 demacro.txt
 Shinobi2
 dev.*
-main.cpp
-sol.scratch.cpp
 lua-5.2.2/
 Debug/
 Release/
@@ -18,3 +15,6 @@ x64/
 *.sln
 *.gitattributes
 liblua.a
+sol/include/
+.ninja*
+include/
diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 00000000..1c1a2167
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "Catch"]
+	path = Catch
+	url = https://github.com/philsquared/Catch.git
diff --git a/Catch b/Catch
new file mode 160000
index 00000000..a6d74bd5
--- /dev/null
+++ b/Catch
@@ -0,0 +1 @@
+Subproject commit a6d74bd55aeff9a2506906e451305364f7a02d34
diff --git a/build.ninja b/build.ninja
new file mode 100644
index 00000000..e574064c
--- /dev/null
+++ b/build.ninja
@@ -0,0 +1,27 @@
+# This file has been generated by shinobi version 0.9.5
+
+ninja_required_version = 1.3
+builddir = bin
+objdir = obj
+cxx = g++
+cxxflags = -std=c++11 -pedantic -pedantic-errors -Wextra -Wall -O2 -DNDEBUG
+incflags = -I"." -I"./include" -I"." -I"/usr/include/lua5.2" -I"./lua-5.2.2/src/" -I"./Catch/include/"
+linkflags = -static -L"./lib" -llua5.2 -ldl
+
+rule compile
+    command = $cxx -MMD -MF $out.d $cxxflags -c $in -o $out $incflags
+    deps = gcc
+    depfile = $out.d
+    description = Compiling $in
+
+rule link
+    command = $cxx $in -o $out $linkflags
+    description = Creating $out
+
+build $objdir/sol.scratch.o: compile sol.scratch.cpp
+
+build $builddir/sol.scratch: link $objdir/sol.scratch.o
+
+build install: phony $builddir/sol.scratch
+
+default install
diff --git a/sol.scratch.cpp b/sol.scratch.cpp
new file mode 100644
index 00000000..3600df44
--- /dev/null
+++ b/sol.scratch.cpp
@@ -0,0 +1,197 @@
+#define CATCH_CONFIG_MAIN
+#include <catch.hpp>
+#include <sol.hpp>
+
+std::string free_function() {
+    std::cout << "free_function()" << std::endl;
+    return "test";
+}
+
+struct object {
+
+    std::string operator() () {
+        std::cout << "member_test()" << std::endl;
+        return "test";
+    }
+
+};
+
+int plop_xyz(int x, int y, std::string z) {
+    std::cout << x << " " << y << " " << z << std::endl;
+    return 11;
+}
+
+TEST_CASE("simple/set_global", "Check if the set_global works properly.") {
+    sol::state lua;
+
+    lua.set("a", 9);
+    REQUIRE_NOTHROW(lua.script("if a ~= 9 then error('wrong value') end"));
+
+    lua.set("d", "hello");
+    REQUIRE_NOTHROW(lua.script("if d ~= 'hello' then error('expected \\'hello\\', got '.. tostring(d)) end"));
+
+    lua.set("e", std::string("hello"));
+    REQUIRE_NOTHROW(lua.script("if d ~= 'hello' then error('expected \\'hello\\', got '.. tostring(d)) end"));
+
+    lua.set("f", true);
+    REQUIRE_NOTHROW(lua.script("if f ~= true then error('wrong value') end"));
+}
+
+TEST_CASE("simple/get", "Tests if the get function works properly.") {
+    sol::state lua;
+
+    lua.script("a = 9");
+    auto a = lua.get<int>("a");
+    REQUIRE(a == 9.0);
+
+    lua.script("b = nil");
+    REQUIRE_NOTHROW(lua.get<sol::nil_t>("b"));
+    
+    lua.script("d = 'hello'");
+    auto d = lua.get<std::string>("d");
+    REQUIRE(d == "hello");
+
+    lua.script("e = true");
+    auto e = lua.get<bool>("e");
+    REQUIRE(e == true);
+}
+
+TEST_CASE("simple/addition", "") {
+    sol::state lua;
+
+    lua.set("b", 0.2);
+    lua.script("c = 9 + b");
+    auto c = lua.get<double>("c");
+
+    REQUIRE(c == 9.2);
+}
+
+TEST_CASE("simple/if", "") {
+    sol::state lua;
+
+    std::string program = "if true then f = 0.1 else f = 'test' end";
+    lua.script(program);
+    auto f = lua.get<double>("f");
+
+    REQUIRE(f == 0.1);
+}
+
+TEST_CASE("simple/callWithParameters", "Lua function is called with a few parameters from C++") {
+    sol::state lua;
+
+    REQUIRE_NOTHROW(lua.script("function my_add(i, j, k) return i + j + k end"));
+    auto f = lua.get<sol::function>("my_add");
+    int a;
+    REQUIRE_NOTHROW(a = f.call<int>(1, 2, 3));
+    REQUIRE(a == 6);
+    REQUIRE_THROWS(a = f.call<int>(1, 2, "arf"));
+}
+
+TEST_CASE("simple/callCppFunction", "C++ function is called from lua") {
+    sol::state lua;
+
+    lua.set_function("plop_xyz", plop_xyz);
+    lua.script("x = plop_xyz(2, 6, 'hello')");
+ 
+    REQUIRE(lua.get<int>("x") == 11);
+}
+
+TEST_CASE("simple/callLambda", "A C++ lambda is exposed to lua and called") {
+    sol::state lua;
+
+    int x = 0;
+
+    lua.set_function("foo", [ &x ] { x = 1; });
+
+    lua.script("foo()");
+
+    REQUIRE(x == 1);
+}
+
+TEST_CASE("advanced/callLambdaReturns", "Checks for lambdas returning values") {
+    sol::state lua;
+
+    lua.set_function("a", [ ] { return 42; });
+    lua.set_function("b", [ ] { return 42u; });
+    lua.set_function("c", [ ] { return 3.14; });
+    lua.set_function("d", [ ] { return 6.28f; });
+    lua.set_function("e", [ ] { return "lol"; });
+    lua.set_function("f", [ ] { return true; });
+    lua.set_function("g", [ ] { return std::string("str"); });
+    lua.set_function("h", [ ] { });
+    lua.set_function("i", [ ] { return sol::nil; });
+}
+
+TEST_CASE("advanced/callLambda2", "A C++ lambda is exposed to lua and called") {
+    sol::state lua;
+
+    int x = 0;
+    lua.set_function("set_x", [ &] (int new_x) {
+        x = new_x;
+        return 0;
+    });
+
+    lua.script("set_x(9)");
+    REQUIRE(x == 9);
+}
+
+TEST_CASE("negative/basicError", "Check if error handling works correctly") {
+    sol::state lua;
+
+    REQUIRE_THROWS(lua.script("nil[5]"));
+}
+
+TEST_CASE("libraries", "Check if we can open libraries through sol") {
+    sol::state lua;
+    REQUIRE_NOTHROW(lua.open_libraries(sol::lib::base, sol::lib::os));
+}
+
+TEST_CASE("tables/variables", "Check if tables and variables work as intended") {
+    sol::state lua;
+    lua.open_libraries(sol::lib::base, sol::lib::os);
+    lua.get<sol::table>("os").set("name", "windows");
+    REQUIRE_NOTHROW(lua.script("assert(os.name == \"windows\")"));    
+}
+
+TEST_CASE("tables/functions_variables", "Check if tables and function calls work as intended") {
+    sol::state lua;
+    lua.open_libraries(sol::lib::base, sol::lib::os);
+    auto run_script = [ ] (sol::state& lua) -> void {
+        lua.script("assert(os.fun() == \"test\")");
+    };
+
+    lua.get<sol::table>("os").set_function("fun",
+        [ ] () {
+            std::cout << "stateless lambda()" << std::endl;
+            return "test";
+        }
+    );
+    REQUIRE_NOTHROW(run_script(lua));
+
+    lua.get<sol::table>("os").set_function("fun", &free_function);
+    REQUIRE_NOTHROW(run_script(lua));
+
+    // l-value, can optomize
+    auto lval = object();
+    lua.get<sol::table>("os").set_function("fun", &object::operator(), lval);
+    REQUIRE_NOTHROW((lua));
+
+    // stateful lambda: non-convertible, unoptomizable
+    int breakit = 50;
+    lua.get<sol::table>("os").set_function("fun",
+        [ &breakit ] () {
+        std::cout << "stateless lambda()" << std::endl;
+        return "test";
+    }
+    );
+    REQUIRE_NOTHROW(run_script(lua));
+
+    // r-value, cannot optomize
+    lua.get<sol::table>("os").set_function("fun", &object::operator(), object());
+    REQUIRE_NOTHROW(run_script(lua));
+
+    // r-value, cannot optomize
+    auto rval = object();
+    lua.get<sol::table>("os").set_function("fun", &object::operator(), std::move(rval));
+    REQUIRE_NOTHROW(run_script(lua));
+}
\ No newline at end of file
diff --git a/sol/function.hpp b/sol/function.hpp
index fcdedc47..49319308 100644
--- a/sol/function.hpp
+++ b/sol/function.hpp
@@ -29,24 +29,28 @@
 namespace sol {
 class function : virtual public reference {
 private:
+    void luacall (std::size_t argcount, std::size_t resultcount) {
+        lua_call(state(), static_cast<uint32_t>(argcount), static_cast<uint32_t>(resultcount));
+    }
+
     template<typename... Ret>
-    std::tuple<Ret...> call(types<Ret...>, std::size_t n) {
-        lua_pcall(state(), n, sizeof...(Ret), 0);
-       return stack::pop_call(state(), std::make_tuple<Ret...>, types<Ret...>());
+    std::tuple<Ret...> invoke(types<Ret...>, std::size_t n) {
+        luacall(n, sizeof...(Ret));
+        return stack::pop_call(state(), std::make_tuple<Ret...>, types<Ret...>());
     }
 
     template<typename Ret>
-    Ret call(types<Ret>, std::size_t n) {
-        lua_pcall(state(), n, 1, 0);
+    Ret invoke(types<Ret>, std::size_t n) {
+        luacall(n, 1);
         return stack::pop<Ret>(state());
     }
 
-    void call(types<void>, std::size_t n) {
-        lua_pcall(state(), n, 0, 0);
+    void invoke(types<void>, std::size_t n) {
+        luacall(n, 0);
     }
 
-    void call(types<>, std::size_t n) {
-        lua_pcall(state(), n, 0, 0);
+    void invoke(types<>, std::size_t n) {
+        luacall(n, 0);
     }
 
 public:
@@ -56,10 +60,10 @@ public:
     }
 
     template<typename... Ret, typename... Args>
-    auto invoke(Args&&... args) -> decltype(call(types<Ret...>(), sizeof...(Args))) {
+    auto call(Args&&... args) -> decltype(invoke(types<Ret...>(), sizeof...(Args))) {
         push();
         stack::push_args(state(), std::forward<Args>(args)...);
-        return call(types<Ret...>(), sizeof...(Args));
+        return invoke(types<Ret...>(), sizeof...(Args));
     }
 };
 } // sol
diff --git a/sol/functional.hpp b/sol/functional.hpp
index 653864db..0ede1e5a 100644
--- a/sol/functional.hpp
+++ b/sol/functional.hpp
@@ -19,11 +19,11 @@
 // IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 // CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-#include "tuple.hpp"
-
 #ifndef SOL_FUNCTIONAL_HPP
 #define SOL_FUNCTIONAL_HPP
 
+#include "tuple.hpp"
+
 namespace sol {
 namespace detail {
 
diff --git a/sol/lua_function.hpp b/sol/lua_function.hpp
index 61a5249d..d98e553b 100644
--- a/sol/lua_function.hpp
+++ b/sol/lua_function.hpp
@@ -29,32 +29,32 @@
 namespace sol {
 namespace detail {
 template<typename T, std::size_t n>
-void get_upvalue_ptr( lua_State* L, T*& data, std::size_t datasize, std::array<void*, n> voiddata, int& upvalue ) {
-	for ( std::size_t i = 0, d = 0; d < datasize; ++i, d += sizeof( void* ) ) {
-		voiddata[ i ] = lua_touserdata( L, lua_upvalueindex( upvalue++ ) );
-	}
-	data = reinterpret_cast<T*>( static_cast<void*>( voiddata.data( ) ) );
+void get_upvalue_ptr(lua_State* L, T*& data, std::size_t datasize, std::array<void*, n> voiddata, int& upvalue) {
+    for (std::size_t i = 0, d = 0; d < datasize; ++i, d += sizeof(void*)) {
+        voiddata[ i ] = lua_touserdata(L, lua_upvalueindex(upvalue++));
+    }
+    data = reinterpret_cast<T*>(static_cast<void*>(voiddata.data()));
 }
 template<typename T, std::size_t n>
-void get_upvalue_ptr( lua_State* L, T*& data, std::array<void*, n> voiddata, int& upvalue ) {
-	get_upvalue_ptr( L, data, sizeof( T ), voiddata, upvalue );
+void get_upvalue_ptr(lua_State* L, T*& data, std::array<void*, n> voiddata, int& upvalue) {
+    get_upvalue_ptr(L, data, sizeof(T), voiddata, upvalue);
 }
 template<typename T>
-void get_upvalue_ptr( lua_State* L, T*& data, int& upvalue ) {
-	const static std::size_t data_t_count = ( sizeof(T)+( sizeof(void*)-1 ) ) / sizeof( void* );
-	typedef std::array<void*, data_t_count> data_t;
-	data_t voiddata{{}};
-	return get_upvalue_ptr(L, data, voiddata, upvalue);
+void get_upvalue_ptr(lua_State* L, T*& data, int& upvalue) {
+    const static std::size_t data_t_count = (sizeof(T)+(sizeof(void*)-1)) / sizeof(void*);
+    typedef std::array<void*, data_t_count> data_t;
+    data_t voiddata{{}};
+    return get_upvalue_ptr(L, data, voiddata, upvalue);
 }
 template<typename T>
-void get_upvalue( lua_State* L, T& data, int& upvalue ) {
-	const static std::size_t data_t_count = ( sizeof(T)+( sizeof(void*)-1 ) ) / sizeof( void* );
-	typedef std::array<void*, data_t_count> data_t;
-	data_t voiddata{ { } };
-	for ( std::size_t i = 0, d = 0; d < sizeof(T); ++i, d += sizeof( void* ) ) {
-		voiddata[ i ] = lua_touserdata( L, lua_upvalueindex( upvalue++ ) );
-	}
-	data = *reinterpret_cast<T*>( static_cast<void*>( voiddata.data( ) ) );
+void get_upvalue(lua_State* L, T& data, int& upvalue) {
+    const static std::size_t data_t_count = (sizeof(T)+(sizeof(void*)-1)) / sizeof(void*);
+    typedef std::array<void*, data_t_count> data_t;
+    data_t voiddata{ { } };
+    for (std::size_t i = 0, d = 0; d < sizeof(T); ++i, d += sizeof(void*)) {
+        voiddata[ i ] = lua_touserdata(L, lua_upvalueindex(upvalue++));
+    }
+    data = *reinterpret_cast<T*>(static_cast<void*>(voiddata.data()));
 }
 } // detail
 
@@ -80,7 +80,7 @@ struct static_lua_func {
     static int call(lua_State* L) {
         int upvalue = 1;
         fx_t* fx;
-	   detail::get_upvalue( L, fx, upvalue );
+        detail::get_upvalue(L, fx, upvalue);
         int r = typed_call(tuple_types<typename fx_traits::return_type>(), typename fx_traits::args_type(), fx, L);
         return r;
     }
@@ -105,8 +105,8 @@ struct static_object_lua_func {
     template<typename TR, typename... Args>
     static int typed_call(types<TR>, types<Args...>, T& item, fx_t& ifx, lua_State* L) {
         auto fx = [ &item, &ifx ] (Args&&... args) -> TR { 
-		   return (item.*ifx)(std::forward<Args>(args)...); 
-	   };
+           return (item.*ifx)(std::forward<Args>(args)...); 
+        };
         auto r = stack::pop_call(L, fx, types<Args...>());
         stack::push(L, std::move(r));
         return 1;
@@ -121,19 +121,19 @@ struct static_object_lua_func {
     }
 
     static int call(lua_State* L) {
-        const static std::size_t data_t_count = ( sizeof(fx_t)+( sizeof(void*)-1 ) ) / sizeof( void* );
-	   typedef std::array<void*, data_t_count> data_t;
-	   int upvalue = 1;
-	   data_t data = { { } };
-	   fx_t* fxptr;
-	   for ( std::size_t i = 0, d = 0; d < sizeof(fx_t*); ++i, d += sizeof( void* ) ) {
-		   data[ i ] = lua_touserdata( L, lua_upvalueindex( upvalue++ ) );
-	   }
-	   fxptr = reinterpret_cast<fx_t*>( static_cast<void*>( data.data( ) ) ); 
-	   fx_t& mem_ptr = *fxptr;
-	   void* objectdata = lua_touserdata( L, lua_upvalueindex( upvalue++ ) );
-	   T& obj = *static_cast<T*>( objectdata );
-	   int r = typed_call( tuple_types<typename fx_traits::return_type>( ), typename fx_traits::args_type( ), obj, mem_ptr, L );
+       const static std::size_t data_t_count = (sizeof(fx_t)+(sizeof(void*)-1)) / sizeof(void*);
+       typedef std::array<void*, data_t_count> data_t;
+       int upvalue = 1;
+       data_t data = { { } };
+       fx_t* fxptr;
+       for (std::size_t i = 0, d = 0; d < sizeof(fx_t*); ++i, d += sizeof(void*)) {
+           data[ i ] = lua_touserdata(L, lua_upvalueindex(upvalue++));
+       }
+       fxptr = reinterpret_cast<fx_t*>(static_cast<void*>(data.data())); 
+       fx_t& mem_ptr = *fxptr;
+       void* objectdata = lua_touserdata(L, lua_upvalueindex(upvalue++));
+       T& obj = *static_cast<T*>(objectdata);
+       int r = typed_call(tuple_types<typename fx_traits::return_type>(), typename fx_traits::args_type(), obj, mem_ptr, L);
         return r;
     }
 
diff --git a/sol/stack.hpp b/sol/stack.hpp
index 1fa8a024..b301072a 100644
--- a/sol/stack.hpp
+++ b/sol/stack.hpp
@@ -45,7 +45,7 @@ inline T get_unsigned(lua_State* L, std::true_type, int index = -1) {
 
 template<typename T>
 inline T get_unsigned(lua_State* L, std::false_type, int index = -1) {
-    return lua_tointeger(L, index);
+    return static_cast<T>(lua_tointeger(L, index));
 }
 
 template<typename T>
@@ -61,11 +61,23 @@ inline T get_arithmetic(lua_State* L, std::true_type, int index = -1) {
 }
 
 template<typename T>
-inline T get_helper(lua_State* L, std::true_type, int index = -1) {
+inline T get_nil(lua_State* L, std::true_type, int index = -1) {
+    if (lua_isnil(L, index) == 0)
+        throw sol::sol_error("not nil");
+    return nil_t{};
+}
+
+template<typename T>
+inline T get_nil(lua_State* L, std::false_type, int index = -1) {
     // T is a class type
     return T(L, index);
 }
 
+template<typename T>
+inline T get_helper(lua_State* L, std::true_type, int index = -1) {
+    return get_nil<T>(L, std::is_same<nil_t, T>(), index);
+}
+
 template<typename T>
 inline T get_helper(lua_State* L, std::false_type, int index = -1) {
     // T is a fundamental type
@@ -184,19 +196,19 @@ inline void push(lua_State* L, const std::array<T, N>& data) {
     }
 }
 
-template <typename T>
-inline int push_user( lua_State* L, T& item ) {
-	typedef typename std::decay<T>::type TValue;
-	const static std::size_t itemsize = sizeof( TValue );
-	const static std::size_t voidsize = sizeof( void* );
-	const static std::size_t voidsizem1 = voidsize - 1;
-	const static std::size_t data_t_count = (sizeof(TValue) + voidsizem1) / voidsize;
-	typedef std::array<void*, data_t_count> data_t;
+template<typename T>
+inline int push_user(lua_State* L, T& item) {
+    typedef typename std::decay<T>::type TValue;
+    const static std::size_t itemsize = sizeof(TValue);
+    const static std::size_t voidsize = sizeof(void*);
+    const static std::size_t voidsizem1 = voidsize - 1;
+    const static std::size_t data_t_count = (sizeof(TValue) + voidsizem1) / voidsize;
+    typedef std::array<void*, data_t_count> data_t;
 
-	data_t data{{}};
-	std::memcpy( std::addressof( data[ 0 ] ), std::addressof( item ), itemsize );
-	push( L, data );
-	return data_t_count;
+    data_t data{{}};
+    std::memcpy(std::addressof(data[ 0 ]), std::addressof(item), itemsize);
+    push(L, data);
+    return data_t_count;
 }
 
 namespace detail {
@@ -215,7 +227,7 @@ auto ltr_pop(lua_State* L, F&& f, types<Head>, Vs&&... vs) -> decltype(ltr_pop(L
     return ltr_pop(L, std::forward<F>(f), types<>(), std::forward<Vs>(vs)..., pop<Head>(L));
 }
 template<typename F, typename Head, typename... Tail, typename... Vs>
-auto ltr_pop(lua_State* L, F&& f, types<Head, Tail...>, Vs&&... vs) -> decltype(ltr_pop(L, std::forward<F>(f), types<Tail...>(), std::forward<Vs>(vs)..., pop<Head>(L))) {
+auto ltr_pop(lua_State* L, F&& f, types<Head, Tail...>, Vs&&... vs) -> decltype(f(std::forward<Vs>(vs)..., std::declval<Head>(), std::declval<Tail>()...)) {
     return ltr_pop(L, std::forward<F>(f), types<Tail...>(), std::forward<Vs>(vs)..., pop<Head>(L));
 }
 } // detail
diff --git a/sol/state.hpp b/sol/state.hpp
index ebd4ced7..a6888cb0 100644
--- a/sol/state.hpp
+++ b/sol/state.hpp
@@ -121,8 +121,8 @@ public:
         }
     }
 
-    void open_file(const std::string& filename) {
-        if(luaL_dofile(L.get(), filename.c_str())) {
+    void script_file(const std::string& filename) {
+        if (luaL_dofile(L.get(), filename.c_str())) {
             lua_error(L.get());
         }
     }
diff --git a/sol/table.hpp b/sol/table.hpp
index bcf635bb..14120adc 100644
--- a/sol/table.hpp
+++ b/sol/table.hpp
@@ -170,7 +170,7 @@ private:
 
         push();
 
-	   int upvalues = stack::push_user( state( ), target );
+       int upvalues = stack::push_user(state(), target);
         luaL_setfuncs(state(), funcreg, upvalues);
 
         lua_pop(state(), 1);
@@ -199,7 +199,7 @@ private:
             lua_settable(state(), -3);
         }
 
-	   push();
+       push();
         stack::push_user(state(), userdata, metatablename);
         luaL_setfuncs(state(), funcreg, 1);