Summary
While building in Retool's new App Builder (Cloud), manual edits to backend function
.tsfiles are not reliably persisting — files revert to older versions or reopen blank after closing/reopening, and the Timeline/Preview keeps running an older synchronized version, even though a frontend test file persisted correctly.AI Response
In the new App Builder, manual code changes are made in the Code tab and are tracked alongside the agent's changes in Change History (agent edits are prefixed with
(Agent)), so an agent regenerating files can overwrite hand-written backend function code. Editing is also locked while critical operations are running and certain platform/agent files are view-only, both of which can cause manual edits to appear not to save. To keep changes durable, make edits in the Code tab only when no agent operation is in progress, confirm the change is recorded in Change History, and avoid editing view-only files. Since manual file management from the Code tab is a recent addition to the new App Builder, reviewing how file creation/editing and change tracking are intended to work is the best way to reconcile this behavior.Sources
Manually edit app code | Retool Docs
Explains manually editing app code in the new App Builder's Code tab, including Change History (agent vs. user edits), view-only files, and edit-locking during critical operations — the mechanisms most likely behind backend function edits reverting or reopening blank.
Retool Team announcement introducing manual file management for the new App Builder's Code tab, confirming this is newly available and pointing to the file-management guidance relevant to persisting backend function changes.
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