A SciScale Studio tool
v0.5.9
the lightest Markdown reader
Vellum is the 5.02 MB local reader for vibe coding — open the Markdown your agent just wrote, check it, edit it, translate it. Upgrade only when you need editing or translation.
The lightest Markdown reader that still feels whole
Vellum is for the moment after an AI agent writes Markdown and before you ship it. Open the file, scan the outline, adjust the reading surface, and upgrade when you want rendered-view editing or translation.
Tiny by design
A local Markdown reader cut down to a 5.02 MB Windows installer. It opens instantly and stays out of the way beside your agent.
Built for the vibe-coding loop
Open the Markdown your agent just wrote, then move through it: follow a link straight into another local file, scan the outline, flip between tabs and recent files, and search — all on your machine.
Edit and translate in place
Vellum adds rendered-view editing and selection translation, so you can fix and localize AI-written docs without leaving the page.
Five reading styles
Reading AI-written Markdown for an hour is easier when the page is yours. Lite ships the two classic themes; Vellum unlocks all five — tuned papers and inks, not just light and dark.
Ivory Manuscript
Light
Lite + VellumNocturne Vellum
Dark
Lite + VellumSage Atelier
Light
VellumGraphite Ember
Dark
VellumRose Quarto
Light
VellumThree editions, one local-first reader
Lite is the free starting point. Vellum is a one-time $5 license that adds the daily revision tools. Lifetime Translate is a one-time $69 license that also removes API-key setup with hosted translation.
Vellum Lite
The tiny local reader to keep beside your agent. No account, no API key, no heavyweight editor.
Vellum
For daily review loops. Keep the lightweight reader, then unlock the tools you reach for when AI-written Markdown needs revision.
Lifetime Translate
For people who want translation to just work. SciScale hosts the translation service so there is no API key to set up.
Hosted translation is in the works — this tier opens soon.
Paid editions are one-time purchases — no subscription. Already bought? Access your downloads.
Get Vellum
Lite installers are hosted directly by SciScale — the Windows NSIS setup is 5.02 MB, measured from the v0.5.9 Lite build. Paid editions check out through SciScale Studio; after purchase you download your licensed Windows and macOS builds from your account.
Vellum Lite
FreeStart here. The smallest reader, two classic themes, and the local Markdown workflow — hosted directly by SciScale.
Also available: Windows .msi (6.54 MB).
Vellum
$5Everything in Lite, plus rendered-view editing, BYO-key translation, and all five reading styles. Pay once, keep it.
After checkout, download your licensed Windows and macOS builds from your account.
Lifetime Translate
$69Everything in Vellum, plus hosted translation managed by SciScale under fair-use limits — no API key to configure.
Hosted translation is in the works — this tier opens soon.
These builds are not code-signed or notarized yet, so Windows SmartScreen or macOS Gatekeeper may ask for confirmation the first time you open them. On Windows choose More info → Run anyway; on macOS right-click the app and choose Open.
File association
Vellum can register itself as the default app for .md, .mdx, and .markdown files on Windows, macOS, and Linux.
Translation, your way
Translation runs through an AI model, not a fixed language-pair service — so it works between any languages and reads the surrounding context, keeping technical terms and code intact. Vellum uses your own OpenRouter or OpenAI-compatible key; Lifetime Translate adds SciScale-hosted translation under fair-use limits — no key to configure.
Unsigned build
The current release is not code-signed or notarized. A smoother first launch needs Windows and Apple signing, which is planned.