diff --git a/packages/react-diagrams-core/src/entities/node/NodeModel.ts b/packages/react-diagrams-core/src/entities/node/NodeModel.ts
index b1c28cd..32a206e 100644
--- a/packages/react-diagrams-core/src/entities/node/NodeModel.ts
+++ b/packages/react-diagrams-core/src/entities/node/NodeModel.ts
@@ -42,7 +42,7 @@ export class NodeModel<G extends NodeModelGenerics = NodeModelGenerics> extends
 	setPosition(point: Point): void;
 	setPosition(x: number, y: number): void;
 	setPosition(x: number | Point, y?: number): void {
-		let old = this.position;
+		const old = this.position;
 
 		if (x instanceof Point) {
 			super.setPosition(x);
diff --git a/packages/react-diagrams-core/src/entities/port/PortModel.ts b/packages/react-diagrams-core/src/entities/port/PortModel.ts
index efd955f..f6d63ce 100644
--- a/packages/react-diagrams-core/src/entities/port/PortModel.ts
+++ b/packages/react-diagrams-core/src/entities/port/PortModel.ts
@@ -1,4 +1,4 @@
-import { NodeModel } from '../node/NodeModel';
+const { NodeModel } from '../node/NodeModel';
 import { LinkModel } from '../link/LinkModel';
 import * as _ from 'lodash';
 import { Point, Rectangle } from '@projectstorm/geometry';
@@ -73,14 +73,14 @@ export class PortModel<G extends PortModelGenerics = PortModelGenerics> extends
 	setPosition(point: Point): void;
 	setPosition(x: number, y: number): void;
 	setPosition(x: number | Point, y?: number): void {
-		let old = this.position;
+		const old = this.position;
 		if (x instanceof Point) {
 			super.setPosition(x);
 		} else {
 			super.setPosition(x, y);
 		}
 		_.forEach(this.getLinks(), (link) => {
-			let point = link.getPointForPort(this);
+			const point = link.getPointForPort(this);
 			point.setPosition(point.getX() + this.getPosition().x - old.x, point.getY() + this.getPosition().y - old.y);
 		});
 	}