GUI Designer who works with a Mac & Sketch

We do design and build complex web apps which are very high quality. We are looking for a 2nd GUI designer who will work as a 2nd designer and work with designs which were created by the lead designer/art director. You will not be a junior designer but you will work under the lead designer. If you have +3 years of experience and own a mac and expert in using Sketch, Please include the keyword "well done" in your bid message and let me know what UI design experience you have and also share your past portfolio. Do not bid if if you are an agency. I will report you for spamming. And also please do not bid if you do not own a mac and don't use Sketch. Looking forward to meet with you if you are a motivated young talent.