diff --git a/src/headers/arguments.hpp b/src/headers/arguments.hpp
index 096928d..bbcd4c9 100644
--- a/src/headers/arguments.hpp
+++ b/src/headers/arguments.hpp
@@ -26,7 +26,7 @@ class ArgumentAssignable: public Argument {
     vector<string_view> values;
 public:
     static string_view getValueFor(const string_view& str) {
-        unsigned long definePos = str.find_last_of('=') + 1;
+        const size_t definePos = str.find_last_of('=') + 1;
         return str.size() > definePos ? str.substr(definePos) : string_view();
     }
     ArgumentAssignable(string name, const span<string_view>& possibleValues): Argument(move(name)), values() {
diff --git a/src/main.cpp b/src/main.cpp
index 799707d..2d44c21 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -64,11 +64,11 @@ int main(int argc, char* argv[]) {
                 try {
                     resultingPair.first = compile(fileName);
                 } catch (const Yerbacon::Exception& error) {
-                    unsigned long lastSlash = 0;
-                    const unsigned long position1 = fileName.find_last_of('/');
+                    size_t lastSlash = 0;
+                    const size_t position1 = fileName.find_last_of('/');
                     if (cmp_not_equal(position1, string_view::npos)) lastSlash = position1;
                     if constexpr(filesystem::path::preferred_separator != '/') {
-                        const unsigned long position2 = fileName.find_last_of(filesystem::path::preferred_separator);
+                        const size_t position2 = fileName.find_last_of(filesystem::path::preferred_separator);
                         if (cmp_not_equal(position2, string_view::npos)) {
                             lastSlash = max(lastSlash, position2);
                         }