diff --git a/model/KeystrokeAction.ts b/model/KeystrokeAction.ts
index 1d55fd7a..87da0e9b 100644
--- a/model/KeystrokeAction.ts
+++ b/model/KeystrokeAction.ts
@@ -5,20 +5,25 @@ class KeystrokeAction implements Serializable {
     private static firstValidScancode = 1;
     private static lastValidScancode = 231;
 
-    scancode: number;
+    _scancode: number;
     modifierMask: number;
 
+    get scancode() {
+        return this._scancode;
+    }
+
+    set scancode(value) {
+        if (!KeystrokeAction.isScancodeValid(value)) {
+            throw 'Scancode ${scancode} is invalid!';
+        }
+        this._scancode = value;
+    }
+
     static isScancodeValid(scancode) {
         return KeystrokeAction.firstValidScancode <= scancode &&
                scancode <= KeystrokeAction.lastValidScancode;
     }
 
-    private static checkScancode(scancode) {
-        if (!KeystrokeAction.isScancodeValid(scancode)) {
-            throw 'Scancode ${scancode} is invalid';
-        }
-    }
-
     fromJsObject(jsObject: any) {
         this.scancode = jsObject.scancode;
         this.modifierMask = jsObject.modifierMask;
@@ -33,7 +38,6 @@ class KeystrokeAction implements Serializable {
 
     fromBinary(buffer: UhkBuffer) {
         this.scancode = buffer.readUInt8();
-        KeystrokeAction.checkScancode(this.scancode);
         this.modifierMask = buffer.readUInt8();
     }
 
diff --git a/model/tsconfig.json b/model/tsconfig.json
index 668b733a..d7bd2173 100644
--- a/model/tsconfig.json
+++ b/model/tsconfig.json
@@ -1,6 +1,7 @@
 {
     "compilerOptions": {
-        "out": "serializeConfig.js"
+        "out": "serializeConfig.js",
+        "target": "es5"
     },
     "files": [
         "typings/main.d.ts",
diff --git a/model/tslint.json b/model/tslint.json
index c008a8b7..1a65cc37 100644
--- a/model/tslint.json
+++ b/model/tslint.json
@@ -83,7 +83,8 @@
         "variable-name": [
             true,
             "ban-keywords",
-            "check-format"
+            "check-format",
+            "allow-leading-underscore"
         ],
         "whitespace": [
             true,