Senior level JavaScript engineering expertise - less focused on Pixel-Perfect development (although an understanding of UX principles and standards is important) and more geared towards "code in the browser "
Expert in ECMA6 / ECMA7. For example:
Promises
Scoping
Literals
Map/Set, WeakMap, WeakSet
Arrow Functions
Typed Arrays
Classes
Destructuring
Expert in CSS& Preprocessorssuch as LESS, Stylus, etc.
Possess a solid understanding of one or more component-based frameworks and their ecosystems (e.g., Vue- ideally - or React).
Have an appreciation for the complexities associated with writing JavaScript SDKs, libraries and third-party integration code. The JS that this Engineer will write will talk directly to Java-based Microservices & RESTfulServices
Will have gained expertise in enterprise-class shops engineering solutions that function at scale. The bigger and cloudier, the better.
Ideal candidate will have worked on Tokenization, Encryption, Signatures, etc. in a JS context
Possesses a Quality Engineering mindset & gladly writes Unit Tests (using tools such as Mocha, Karma, Protractor, Cucumber, Jasmine, etc.)
NO JS Ninjas, Script Kiddies or Web Vikings. We're talking about true Engineers who have plowed their programming career furrow using JS as opposed to Java, C#, et al