diff --git a/Makefile b/Makefile
index 8f8cd56..3313372 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 all: build-windows build-linux
 
 build-windows:
-	env GOOS=windows GOARCH=amd64 go build -o ./build/eu4-checksum-patcher-windows.exe *.go 
+	env GOOS=windows GOARCH=amd64 go build -o ./build/universal-checksum-patcher-windows.exe *.go 
 
 build-linux:
-	env GOOS=linux GOARCH=amd64 go build -o ./build/eu4-checksum-patcher-linux *.go 
\ No newline at end of file
+	env GOOS=linux GOARCH=amd64 go build -o ./build/universal-checksum-patcher-linux *.go 
\ No newline at end of file
diff --git a/go.mod b/go.mod
index c78eacb..21b9fd7 100644
--- a/go.mod
+++ b/go.mod
@@ -1,3 +1,10 @@
 module github.com/goshathebusiness/eu4-checksum-patcher
 
 go 1.19
+
+require github.com/manifoldco/promptui v0.9.0
+
+require (
+	github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e // indirect
+	golang.org/x/sys v0.0.0-20181122145206-62eef0e2fa9b // indirect
+)
diff --git a/go.sum b/go.sum
index e69de29..34fdb2a 100644
--- a/go.sum
+++ b/go.sum
@@ -0,0 +1,10 @@
+github.com/chzyer/logex v1.1.10 h1:Swpa1K6QvQznwJRcfTfQJmTE72DqScAa40E+fbHEXEE=
+github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
+github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e h1:fY5BOSpyZCqRo5OhCuC+XN+r/bBCmeuuJtjz+bCNIf8=
+github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
+github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1 h1:q763qf9huN11kDQavWsoZXJNW3xEE4JJyHa5Q25/sd8=
+github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMnBNeIyt5eFwwo7qiLfzFZmjNmxjkiQlU=
+github.com/manifoldco/promptui v0.9.0 h1:3V4HzJk1TtXW1MTZMP7mdlwbBpIinw3HztaIlYthEiA=
+github.com/manifoldco/promptui v0.9.0/go.mod h1:ka04sppxSGFAtxX0qhlYQjISsg9mR4GWtQEhdbn6Pgg=
+golang.org/x/sys v0.0.0-20181122145206-62eef0e2fa9b h1:MQE+LT/ABUuuvEZ+YQAMSXindAdUh7slEmAkup74op4=
+golang.org/x/sys v0.0.0-20181122145206-62eef0e2fa9b/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
diff --git a/main.go b/main.go
index 6a4da96..52c2934 100644
--- a/main.go
+++ b/main.go
@@ -1,12 +1,40 @@
 package main
 
-import "runtime"
+import (
+	"fmt"
+	"runtime"
+
+	"github.com/manifoldco/promptui"
+)
 
 func main() {
 
-	originalFileName := "eu4"
-	finalFileName := "eu4"
+	prompt := promptui.Select{
+		Label: "Select game to patch",
+		Items: []string{"Europa Universalis IV", "Hearts of Iron IV"},
+	}
+
+	_, result, err := prompt.Run()
+
+	if err != nil {
+		fmt.Printf("Prompt failed %v\n", err)
+		return
+	}
+
+	switch result {
+	case "Europa Universalis IV":
+		err = applyPatch(false, "eu4", runtime.GOOS)
+	case "Hearts of Iron IV":
+		err = applyPatch(false, "hoi4", runtime.GOOS)
+	}
 
-	applyPatch(false, originalFileName, finalFileName, runtime.GOOS)
+	if err != nil {
+		fmt.Println("ERROR:", err)
+		fmt.Println("Patch not installed, no file has been changed")
+	} else {
+		fmt.Println("Patch successfully installed, your original executable has been backuped in [original name]_backup")
+	}
+	fmt.Println("Press enter to exit")
+	fmt.Scanln()
 
 }
diff --git a/patch.go b/patch.go
index 4a720f8..488d86e 100644
--- a/patch.go
+++ b/patch.go
@@ -52,16 +52,48 @@ func compareExes(exeAName, exeBName string) bool {
 	return reflect.DeepEqual(byteA, byteB)
 }
 
-func applyPatch(test bool, originalFileName, finalFileName, OS string) error {
+func applyPatch(test bool, originalFileName, OS string) error {
 
 	var fileExtension string
 	var hexExists []string
 	var hexWanted []string
-	hexExistsWindows := []string{"48", "8D", "0D", "??", "??", "??", "01", "E8", "??", "??", "??", "01", "85", "C0", "0F", "94", "C3", "E8", "97", "79", "E9"}
-	hexWantedWindows := []string{"48", "8D", "0D", "??", "??", "??", "01", "E8", "??", "??", "??", "01", "31", "C0", "0F", "94", "C3", "E8", "97", "79", "E9"}
+	var hexExistsWindows []string
+	var hexWantedWindows []string
+	var hexExistsLinux []string
+	var hexWantedLinux []string
+	// EU4
+	hexExistsEU4Windows := []string{"48", "8D", "0D", "??", "??", "??", "01", "E8", "??", "??", "??", "01", "85", "C0", "0F", "94", "C3", "E8", "97", "79", "E9"}
+	hexWantedEU4Windows := []string{"48", "8D", "0D", "??", "??", "??", "01", "E8", "??", "??", "??", "01", "31", "C0", "0F", "94", "C3", "E8", "97", "79", "E9"}
+	hexExistsEU4Linux := []string{"E8", "65", "95", "E5", "FF", "89", "C3", "E8", "38", "08", "EC", "FF", "31", "F6", "85", "DB", "40", "0F", "94", "C6", "48", "89", "C7"}
+	hexWantedEU4Linux := []string{"E8", "65", "95", "E5", "FF", "89", "C3", "E8", "38", "08", "EC", "FF", "31", "F6", "31", "DB", "40", "0F", "94", "C6", "48", "89", "C7"}
+	// HOI4
+	hexExistsHOI4Windows := []string{"48", "8D", "0D", "77", "B6", "C9", "01", "E8", "CA", "86", "B3", "01", "85", "C0", "0F", "94", "C3", "E8", "90"}
+	hexWantedHOI4Windows := []string{"48", "8D", "0D", "77", "B6", "C9", "01", "E8", "CA", "86", "B3", "01", "31", "C0", "0F", "94", "C3", "E8", "90"}
+	hexExistsHOI4Linux := []string{}
+	hexWantedHOI4Linux := []string{}
+
+	if strings.Contains(originalFileName, "eu4") {
+		hexExistsWindows = hexExistsEU4Windows
+		hexWantedWindows = hexWantedEU4Windows
+
+		hexExistsLinux = hexExistsEU4Linux
+		hexWantedLinux = hexWantedEU4Linux
+	} else if strings.Contains(originalFileName, "hoi4") {
+		if OS == "linux" {
+
+			return errors.New("patching linux version of Hearts of Iron IV is not currently supported")
+		}
+
+		hexExistsWindows = hexExistsHOI4Windows
+		hexWantedWindows = hexWantedHOI4Windows
+
+		hexExistsLinux = hexExistsHOI4Linux
+		hexWantedLinux = hexWantedHOI4Linux
+
+	} else {
+		return errors.New("not supported executable")
+	}
 
-	hexExistsLinux := []string{"E8", "65", "95", "E5", "FF", "89", "C3", "E8", "38", "08", "EC", "FF", "31", "F6", "85", "DB", "40", "0F", "94", "C6", "48", "89", "C7"}
-	hexWantedLinux := []string{"E8", "65", "95", "E5", "FF", "89", "C3", "E8", "38", "08", "EC", "FF", "31", "F6", "31", "DB", "40", "0F", "94", "C6", "48", "89", "C7"}
 	switch OS {
 	case "windows":
 		fileExtension = ".exe"
@@ -73,15 +105,12 @@ func applyPatch(test bool, originalFileName, finalFileName, OS string) error {
 		hexWanted = hexWantedLinux
 	default:
 		fileExtension = ""
-		fmt.Printf("ERROR: This OS is not supported")
-		fmt.Println("Press enter to exit")
-		fmt.Scanln()
-		return errors.New("This OS is not supported")
+		return fmt.Errorf("this OS (%s) is not supported", OS)
+
 	}
 
 	byteExists := make([]byte, len(hexExists))
 	byteWanted := make([]byte, len(hexWanted))
-
 	for i, h := range hexExists {
 		var value int64
 		if h == "??" {
@@ -106,13 +135,9 @@ func applyPatch(test bool, originalFileName, finalFileName, OS string) error {
 	}()
 
 	if _, err := os.Stat(originalFileName + fileExtension); errors.Is(err, os.ErrNotExist) {
-		fmt.Printf("ERROR: Cannot locate %s in current folder\n", originalFileName+fileExtension)
-		if !test {
-			fmt.Println("Press enter to exit")
-			fmt.Scanln()
-		}
-		return errors.New("Cant find executable file")
+		return fmt.Errorf("cannot locate %s in current folder", originalFileName+fileExtension)
 	}
+
 	originalByte, err := os.ReadFile(originalFileName + fileExtension)
 	if err != nil {
 		return err
@@ -123,13 +148,9 @@ func applyPatch(test bool, originalFileName, finalFileName, OS string) error {
 	matchesNeeded := len(byteExists)
 	matches := 0
 	status := false
-	if !test {
-		fmt.Println("Patching process started")
-	}
 
 	for i := 0; i < len(finalByte); i++ {
-
-		if finalByte[i] == byteExists[0] && finalByte[i+len(byteExists)-1] == byteExists[len(byteExists)-1] {
+		if finalByte[i] == byteExists[0] {
 			matches++
 			for j := range byteExists {
 				if (finalByte[i+j] == byteExists[j]) || (byteExists[j] == 0) {
@@ -140,31 +161,25 @@ func applyPatch(test bool, originalFileName, finalFileName, OS string) error {
 				}
 			}
 			if matches >= matchesNeeded {
-				if !test {
-					fmt.Println("Needed byte-combination finded")
-				}
 				for k := range byteExists {
 					if byteExists[k] != 0 {
 						finalByte[i+k] = byteWanted[k]
 					}
 				}
 				status = true
+
 				break
 			}
 		}
 	}
 
 	if !status {
-		fmt.Printf("ERROR: Unsupported version of %s or it's patched already. Patch has not been applied\n", originalFileName+fileExtension)
+
 		os.Remove(originalFileName + "_backup" + fileExtension)
-		if !test {
-			fmt.Println("Press enter to exit")
-			fmt.Scanln()
-		}
-		return errors.New("Cant apply patch")
+		return fmt.Errorf("unsupported version of %s or it's patched already. Patch has not been applied", originalFileName+fileExtension)
 	}
 
-	out, err := os.Create(finalFileName + fileExtension)
+	out, err := os.Create(originalFileName + fileExtension)
 	if err != nil {
 		return err
 	}
@@ -172,10 +187,5 @@ func applyPatch(test bool, originalFileName, finalFileName, OS string) error {
 	out.Write(finalByte)
 	out.Close()
 
-	fmt.Printf("%s successfully patched\n", originalFileName+fileExtension)
-	if !test {
-		fmt.Println("Press enter to exit")
-		fmt.Scanln()
-	}
 	return nil
 }
diff --git a/patch_test.go b/patch_test.go
deleted file mode 100644
index ce0baf3..0000000
--- a/patch_test.go
+++ /dev/null
@@ -1,48 +0,0 @@
-package main
-
-import (
-	"os"
-	"testing"
-)
-
-func TestApplyPatchWindows(t *testing.T) {
-	t.Parallel()
-	err := backupFile("./test_files/eu4_original.exe", "./test_files/eu4_test.exe")
-
-	if err != nil {
-		t.Error(err)
-	}
-	err = applyPatch(true, "./test_files/eu4_test", "./test_files/eu4_test", "windows")
-
-	if err != nil {
-		t.Error(err)
-	}
-
-	if !compareExes("./test_files/eu4_patched.exe", "./test_files/eu4_test.exe") {
-		if err != nil {
-			t.Error("Executables doesnt match")
-		}
-	}
-	os.Remove("./test_files/eu4_test.exe")
-}
-
-func TestApplyPatchLinux(t *testing.T) {
-	t.Parallel()
-	err := backupFile("./test_files/eu4_original", "./test_files/eu4_test")
-
-	if err != nil {
-		t.Error(err)
-	}
-	err = applyPatch(true, "./test_files/eu4_test", "./test_files/eu4_test", "linux")
-	if err != nil {
-		t.Error(err)
-	}
-
-	if !compareExes("./test_files/eu4_patched", "./test_files/eu4_test") {
-		if err != nil {
-			t.Error("Executables doesnt match")
-		}
-	}
-	os.Remove("./test_files/eu4_test")
-
-}
diff --git a/test_eu4_patch_test.go b/test_eu4_patch_test.go
new file mode 100644
index 0000000..aa59301
--- /dev/null
+++ b/test_eu4_patch_test.go
@@ -0,0 +1,50 @@
+package main
+
+import (
+	"os"
+	"testing"
+)
+
+func TestApplyPatchEU4Windows(t *testing.T) {
+	err := backupFile("./test_files/eu4/eu4_original.exe", "./test_files/eu4/eu4_test.exe")
+
+	if err != nil {
+		t.Error(err)
+	}
+	err = applyPatch(true, "./test_files/eu4/eu4_test", "windows")
+
+	if err != nil {
+		t.Error(err)
+	}
+
+	if !compareExes("./test_files/eu4/eu4_patched.exe", "./test_files/eu4/eu4_test.exe") {
+		if err != nil {
+			t.Error("Executables doesnt match")
+		}
+	}
+	os.Remove("./test_files/eu4/eu4_test.exe")
+	os.Remove("./test_files/eu4/eu4_test_backup.exe")
+	os.Remove("./test_files/eu4/eu4.exe")
+}
+
+func TestApplyPatchEU4Linux(t *testing.T) {
+	err := backupFile("./test_files/eu4/eu4_original", "./test_files/eu4/eu4_test")
+
+	if err != nil {
+		t.Error(err)
+	}
+	err = applyPatch(true, "./test_files/eu4/eu4_test", "linux")
+	if err != nil {
+		t.Error(err)
+	}
+
+	if !compareExes("./test_files/eu4/eu4_patched", "./test_files/eu4/eu4_test") {
+		if err != nil {
+			t.Error("Executables doesnt match")
+		}
+	}
+	os.Remove("./test_files/eu4/eu4_test")
+	os.Remove("./test_files/eu4/eu4_test_backup")
+	os.Remove("./test_files/eu4/eu4")
+
+}
diff --git a/test_hoi4_patch_test.go b/test_hoi4_patch_test.go
new file mode 100644
index 0000000..7a7c20c
--- /dev/null
+++ b/test_hoi4_patch_test.go
@@ -0,0 +1,50 @@
+package main
+
+import (
+	"os"
+	"testing"
+)
+
+func TestApplyPatchHOI4Windows(t *testing.T) {
+	err := backupFile("./test_files/hoi4/hoi4_original.exe", "./test_files/hoi4/hoi4_test.exe")
+
+	if err != nil {
+		t.Error(err)
+	}
+	err = applyPatch(true, "./test_files/hoi4/hoi4_test", "windows")
+
+	if err != nil {
+		t.Error(err)
+	}
+
+	if !compareExes("./test_files/hoi4/hoi4_patched.exe", "./test_files/hoi4/hoi4_test.exe") {
+		if err != nil {
+			t.Error("Executables doesnt match")
+		}
+	}
+	os.Remove("./test_files/hoi4/hoi4_test.exe")
+	os.Remove("./test_files/hoi4/hoi4_test_backup.exe")
+	os.Remove("./test_files/hoi4/hoi4.exe")
+}
+
+// func TestApplyPatchHOILinux(t *testing.T) {
+// 	err := backupFile("./test_files/hoi4/hoi4_original", "./test_files/hoi4/hoi4_test")
+
+// 	if err != nil {
+// 		t.Error(err)
+// 	}
+// 	err = applyPatch(true, "./test_files/hoi4/hoi4_test", "linux")
+// 	if err != nil {
+// 		t.Error(err)
+// 	}
+
+// 	if !compareExes("./test_files/hoi4/hoi4_patched", "./test_files/hoi4/hoi4_test") {
+// 		if err != nil {
+// 			t.Error("Executables doesnt match")
+// 		}
+// 	}
+// 	os.Remove("./test_files/hoi4/hoi4_test")
+// 	os.Remove("./test_files/hoi4/hoi4_test_backup")
+// 	os.Remove("./test_files/hoi4/hoi4")
+
+// }