Local Deno Development with FlyEnv

Deno is a runtime for JavaScript and TypeScript built on V8, created by the original author of Node.js, with built-in TypeScript support and a default-deny permission model. It is used for servers, scripts and tooling where a single self-contained binary is convenient. FlyEnv's Deno module is deliberately focused: it installs Deno versions, decides which one your terminal deno command resolves to, and binds each project to its own runtime. The module has three tabs — Projects, Service and Version Manager — covering version installation, PATH control and project runtimes, with no configuration files or log viewers to manage.

Deno version management

Install Deno versions side by side from Deno → Version Manager and keep them all available at once.

• Static builds: an online list of Deno packages is available on every platform; FlyEnv downloads each version into its own app directory (deno/<version>) and removes the macOS quarantine attribute automatically.
• Homebrew (macOS and Linux): install the deno formula. Homebrew publishes only this unversioned formula, so there are no [email protected] versioned variants to pick from.
• Custom directories: point FlyEnv at any directory containing your own Deno build; it detects the version by running deno --version and lists the binary next to the managed versions.

Command-line version switching

The Service tab starts nothing — Deno is a runtime binary rather than a daemon, so what this tab actually shows is a version and PATH management table.

• Terminal version switching: pick the installed version your terminal deno command should resolve to. FlyEnv adds or removes the version's bin directory in your PATH accordingly and indicates whether the current PATH entry belongs to FlyEnv or to another tool. The system PATH environment guide explains this PATH editing in detail.
• Per-version alias and remark: each installation accepts a short alias and a note, keeping similar builds distinguishable in the list.
• Housekeeping: the table surfaces each version's install path and lets you delete versions you no longer need.

Project-level Deno runtimes

In Deno → Projects, register each project folder and bind it to a specific Deno version instead of relying on whichever version happens to be in PATH.

• Per-project runtime: the version choice is stored in a .flyenv file inside the project directory, so terminals and editors launched from FlyEnv pick up the right Deno automatically. See the project-level runtime environment guide and the Per-Project Runtimes feature for how the mechanism works.
• Run as service: optionally run a project directly from FlyEnv with a custom start command; the project link is a plain http://127.0.0.1:<port> address, with no reverse-proxy or site integration.
• Open-in tools: jump from a project row into a terminal or editor with the project environment loaded.

Related guides, solutions and demos

Continue with a practical guide, solution, demo, or community perspective.

Guides

• Project-level runtime isolation
• System PATH management
• Deploy Node.js, Python and Go without Docker

Demos

• Browse runtime demos

Compatibility Notes

FlyEnv manages Deno version installation, PATH switching and project runtimes; it does not bundle Deno tooling beyond what each Deno build itself provides, and the module has no config editor, log viewer or admin panel. Available install sources differ per platform — Homebrew is macOS and Linux only, and Windows uses Static builds plus custom directories — so treat the Download page and current release notes as the source for supported packages.