Ask HN: What companies and or Gov agencies support 100% remote positions?

I currently work 100% remote for a small company. I am curious what larger companies support remote work. I am well-aware of https://weworkremotely.com/ and https://remoteok.io/ type websites. For example 18F posted here the other day, they allow remote. I have heard Twitter and Salesforce have some small fully remote teams. Please chime in.