# Helix 1.21.1: Windows dev server fix

> Fixes a bug where `helix dev` failed to start on Windows due to incorrect file-path handling.

- Released: 5 Nov 2026 (2026-11-05)
- Packages: @trayai/helix-cli@1.21.1

## Headline changes

### Fixed: `helix dev` mishandled Windows file paths, which prevented the local dev server from starting…

`helix dev` now correctly handles Windows file paths. Previously, the local dev server could fail to start on Windows because path separators were not resolved properly. If you develop on Windows and hit startup errors with `helix dev`, upgrading to this release resolves the issue.

Docs: https://helix.tray.ai/documentation/reference/cli/dev/

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Canonical: https://helix.tray.ai/documentation/releases/1211/
This file: https://helix.tray.ai/documentation/releases/1211.md
The full changelog: https://helix.tray.ai/documentation/releases.md