one dev

one dev reads each project's development command from the manifest and runs it through One CLI's built-in supervisor.

Usage

one dev [project] [--dry-run]

Options

option	purpose
positional `project`	start one project by manifest `name` or `relativeDir`
`-p`, `--project <name	path>`
`--dry-run`	print the supervisor command without starting processes
`-o`, `--output <fmt>`	`json` / `yaml` / `text`

Dependency preparation

one dev prepares the selected projects before starting any development commands. Interactive and non-interactive calls use the same preparation flow.

Node dependencies are prepared at the workspace root. With pnpm 10.14 or later, One asks pnpm to verify the installed workspace state and reuses a matching installation, including one created by a manual pnpm install. When installation is needed, it runs pnpm install --no-frozen-lockfile so new projects and dependency changes can update the lockfile. Older pnpm versions use One's installation cache. Other package managers keep their existing lockfile policy.
one build keeps the strict installation policy: an existing pnpm dependency lockfile uses --frozen-lockfile. If it is stale, install dependencies and review the lockfile changes before building.
Go preparation downloads the fixed module build list or resolves workspace dependencies, maintaining checksums as needed. It does not run go mod tidy or go work sync automatically.
A failed preparation stops startup. Package-manager diagnostics are streamed once; canceling stops the preparation process. one run does not install dependencies.

Runner

One CLI's built-in supervisor starts all developable projects by default, or one positional project.

one dev
one dev web
one dev apps/web --dry-run

Common errors

code	fix
`RUN_COMMAND_NOT_FOUND`	check the native tools or mise configuration
`ONE_CLI_ERROR`	fix the reported dependency error, then retry
`SUBPROJECT_NOT_FOUND`	use a project `name` or `relativeDir`