Renest

comfyui-renest

Nest a working run — save its files and dependencies, checked byte for byte.

Renest saves a ComfyUI or fine-tuning setup that already worked on a rented GPU — the model files, custom nodes, exact package versions and workflow — and brings it back on another Linux GPU machine, every file checked against its SHA-256. It promises that the files and dependencies come back verified; whether the app then runs is tested on every restore and reported, not promised.

This is the official Renest panel for ComfyUI. The moment a run succeeds, Nest this run saves everything that run depended on — models, custom nodes, dependency versions, the workflow itself — into a single open-format archive (a "nest") on this machine's disk and checks every file byte for byte. Then you choose: Save to my Renest drive uploads it once you approve that upload in your browser (the drive needs a paid subscription), or Save on this machine only keeps it on this disk, free, with no account needed. Restore it later on another machine and those files and dependencies come back, checked again against the same fingerprints. Docs: https://renest.ai/docs/plugin-nest-this-run

What it looks like

• A Renest tab in the ComfyUI sidebar.
• After a successful run: Nest this run → a preview of exactly what will be saved (models / ComfyUI itself / custom nodes / dependency locks, with sizes), anything that could not be captured, and where the nest will be written → one of two buttons:
  • Save to my Renest drive → a short code to approve in your browser → live progress until it is saved, checked and on your Renest drive. The drive needs a subscription; if your plan has none, or the drive is full, the panel says so, links to the plans page, and offers Save on this machine instead.
  • Save on this machine only → the same pack, kept on this disk. Free, no sign-in. On a rented machine it is gone when the machine is, unless you copy the folder off.
• If the Renest engine isn't installed yet, the tab shows the two commands that install it. Nothing else to configure.

Nest this run / Take back

Nest this run only takes the workflow that just ran to the end: what a nest is worth is what that run used, caught while it worked. A canvas that has not run, or has changed since its last run finished, gets "run it once first" instead. Once the drive has checked an upload, the panel lists the model files it now holds, so you can free the space yourself — Renest never deletes anything in your ComfyUI folder. Take back (approved once in your browser) lists your saved workflows, compares one with this machine — ComfyUI, Python, torch, custom nodes, files — and brings the missing files back, checked byte for byte. A file that is already here with different bytes is kept; ours lands beside it. It does not install custom nodes, and it does not promise the workflow will run.

Install

Via ComfyUI-Manager: search for "Renest", install, restart ComfyUI.

Manually:

cd ComfyUI/custom_nodes
git clone https://github.com/renest-ai/comfyui-renest

Then install the Renest engine (any terminal, once per machine):

uv tool install --upgrade renest
# no uv yet?  curl -LsSf https://astral.sh/uv/install.sh | sh
#             or:  pip install uv   (a single binary, no dependencies —
#             safe to run inside this ComfyUI environment)
# or, if you know this environment is separate: pip install renest
renest login
renest serve

renest login is only needed for the Renest drive (no account yet? create one at https://app.renest.ai/register). It signs this machine in to your Renest account: it prints a page and a code, you approve them in your browser, and the machine keeps a sign-in that can only ask for an upload. Every upload from the panel is then approved by you, once, in your own browser.

The engine is a separate program with its own licence (source-available: the code is public to read and audit, but it is not open source; its escape hatch and the nest format specs are Apache-2.0). It listens on 127.0.0.1:7799 and nothing else.

Where the nest is saved

Next to the environment it came from: <the folder holding your ComfyUI>/renest-nests/. The panel shows the exact path both before you commit to it and once the nest is done, so you can back it up, move it, or hand it to someone else. That folder sits on the same disk as your models, which on a rented pod is the volume that survives a restart — a home directory there often does not.

How it works, and what never happens

• The panel works on a rented machine, opened from your own browser. The browser only ever talks to ComfyUI's own address (/renest/api/...). The panel's Python half, running next to ComfyUI, passes each call on to the engine over loopback HTTP only (127.0.0.1:7799 on that machine). It never imports the engine's code: the process boundary is also the licence boundary.
• The engine's token never reaches your browser. The Python half reads it from the file the engine writes on that machine and adds it to each call it passes on.
• Only the calls the panel needs are passed on: check the engine, preview and pack, follow and cancel that job; for Take back, open a session you approve in your browser, compare or fetch one saved workflow, and close the session. Which folder gets packed, where the nest is written and where taken-back files land are decided on the machine, never by what the browser sends; the browser only picks the workflow, its name, and drive or this machine. Anyone who can open your ComfyUI can use the panel too, so keep that address to yourself.
• No cloud credentials pass through here. Bucket keys and account tokens are the engine's business; this panel never sees, stores or forwards them.
• Nothing is uploaded without your approval. A nest is written to your own disk first, and Save on this machine only uploads nothing. Each upload to your Renest drive asks for your approval in your own browser, from the account this machine was signed in to; the permission it gets covers that one upload only and is withdrawn when it ends. The machine keeps nothing that can upload by itself.
• Nests carry no absolute paths from your machine. The archive records where things go relative to the environment, not where they came from — so handing a nest to someone else does not hand over your folder layout or your user name.

Requirements

• ComfyUI with the sidebar extension API (frontend 1.4x or newer).
• The renest Python package (>= 0.1.0) running renest serve on the same machine. Any regular Python 3.11+ can host it — it does not have to be the interpreter that runs ComfyUI. On the Windows portable build, install it with a normal Python rather than the embedded one, which ships without pip on PATH.

Licence

Copyright (C) 2026 Tensor Logic Digital, LLC.

GPL-3.0-or-later. This extension runs inside ComfyUI's process, so it follows ComfyUI's licence. The Renest engine it talks to is a separate program under its own source-available licence (shipped as the LICENSE-CLI file of the renest package); only the engine's escape hatch and the nest format specs are Apache-2.0.

The hosted Renest service at renest.ai is operated by the authors of this project.