Levels.fyi - Compare career levels across software eng and other fields
LinkedIn Recruiter - LinkedIn Recruiter is a recruiting tool to hire talent from LinkedIn.
Caliber - IM for LinkedIn. Instantly chat with your business contacts.
Lever - A modern web app for hiring. Lever is a simple, powerful way to manage lists of candidates during the hiring process.
whoishiring.io - Making the IT job search simpler and more effective
Greenhouse - Greenhouse Software makes companies great at hiring.