Finding a Data Race in rancher/remotedialer, Then Pinning Only Two-Thirds of the Fix

Tue, 01 Sep 2026 21:05:00 -0700

shipmates ships connect to Fleet Command over outbound websocket tunnels. That way nothing on the ship side has to be exposed to the internet. I didn’t write that tunnel layer. I used rancher/remotedialer, the same library Rancher uses to reach downstream cluster agents. I spent years around that code at Rancher, so it was the obvious pick. What I didn’t expect was for my CI’s race job to find two data races in it in the first week.

Rancher on Luther Monson

Finding a Data Race in rancher/remotedialer, Then Pinning Only Two-Thirds of the Fix