Hacker News on 19 January 2018

• LuLu: An open-source macOS firewall that blocks unknown outgoing connections
• Reality has a surprising amount of detail (2017)
• Is it time for open processors?
• Laws of UX
• Programming Notes for Professionals books
• List of oldest companies: Before 1300
• Embedded in Rust: Brave new I/O
• An Amazon Order Might Lock You Out of Trusted Traveler Programs
• Trial of a blood test that detects eight common forms of cancer
• U.S. tests nuclear power system to sustain astronauts on Mars