From an HN comment:

Impactful?

Designed and deployed credit card readers used in gas pumps back in 1979. (Sold to Gasboy)

Wrote a fine tuner to allow communication between satellites (precursor to TDRSS days). Still used to this day.

Failover of IP in ATM switches (VVRP, PXE, secondary DHCP, secondary DNS, secondary LDAP, secondary NFS). While not invented here, it is still used today as this is a Common setup to this day.

Printer drivers for big, big high-speed Xerox printers on BSD. Still used to this day by big, big high-speed printers.

Also, early IDS products (pre-Snort) at line-speed. Sold to Netscreen.

Easy zero-setup of DSL modem before some BellCore decided to complicate things (thus exploding their field deployment budgets; Southwestern Bell/Qwest enjoyed our profitable zero-setup). Sold to Siemens.

1Gps IDS/IPS before selling it to 3Com/Hewlett-Packard Packard.

Now, I'm dabbling in a few startups (JavaScript HIDS, Silent Connections, replacing the systemd-temp).

Impact? It is more about personal pride but its impacts are still being felt today.

Dunno who this person is, but I’ll be lucky to feel I’ve don a fraction of this.