Background Agent clock discrepancy preventing apt-get update

Describe the Bug

Hi there - I’ve been running into issues with background agents today. It is failing during environment setup - and I’ve narrowed it down to the system clock being off by several+ hours on the container – and that causing apt-get commands to fail.

Has anyone ran into this before and/or have any suggested work arounds?

Steps to Reproduce

  1. Configure your project to use a custom Dockerfile (via .cursor/environment.json)
  2. Use a stripped down Dockerfile like:
FROM ubuntu:24.04
RUN date
RUN apt-get update -y

Expected Behavior

  • Date should return an up to date timestamp (instead its 12+ hours behind)
  • Apt-get update should work (not have package list release file “is not valid yet” errors)
  • Dockerfile is able to continue with install packages with apt-get thereafter

Screenshots / Screen Recordings

Operating System

Linux

Current Cursor Version (Menu → About Cursor → Copy)

I’m primarily debugging this on the Web UI for Agents

Additional Information

I’ve been in the process of enabling out Background Agent setup for our projects for the first time - so I can’t speak to whether this is a recent regression or something that has been ongoing.

Additionally I tried different approaches to syncing time - but none of the services or utilities to do this come preinstalled on the minimal container env - and there isn’t permissions to set date time in the container.

Does this stop you from using Cursor

Yes - Cursor is unusable