nono is great but you'll still won't be able to run multiple dev servers, dbs or test in the browser...
the better alternative is using sandboxes, for TRUE isolation.
but most people skip them because it's harder to set up a dev environment in a sandbox, for this I built agentbox [1], a tool to teleport your files, skills, settings, claude/codex subscriptions etc in any of the popular sandboxes. eg:
agentbox e2b claude
or:
agentbox hetzner codex
each session is persistent, with a full VM, with a browser, webVNC screen sharing and local https tunnel for easy preview on *.localhost domains.
Also git credentials never leave your pc: when a box needs access it passes through the agentbox service running on your machine, which allows PR creations, comments but only on the box branch, no deletion etc.