Last reviewed: March 2026
MarkLayer is built and maintained by Vadym Rusin, a software engineer who works on browser extensions, real-time collaboration, and Cloudflare's edge platform. This page exists so you know who is behind the comparisons, alternatives, and use-case guides on this site, and how the editorial work is done.
I'm a software engineer focused on browser extensions, real-time collaboration, and Cloudflare's edge platform (Workers, Durable Objects, D1, R2). I read and write Preact, TypeScript, Hono, and Cloudflare's Workers runtime daily. MarkLayer started as a tool I wanted for design review and visual feedback on live pages and turned into the public free + anonymous version you're looking at now.
The full source is on GitHub. Anyone can read it, file issues, or self-host their own instance on Cloudflare. Reach me at rusinvadym@gmail.com or via GitHub Issues.
MarkLayer's stack is public. The Chrome extension is built with WXT and Preact + Preact Signals. The backend is Cloudflare Workers (Hono framework), with a Durable Object per share session for real-time WebSocket fan-out, D1 (SQLite at the edge) for annotation persistence, and R2 for OG image storage. The choice of stack is itself an editorial position: free, open-source software that runs on a low-cost edge platform is what makes the "no paid plan, ever" promise structurally credible.
Comparison and alternatives pages on this site are written from hands-on use, public documentation, and competitor pricing pages at the time of last review. When MarkLayer is genuinely the wrong fit for a workflow, the relevant page says so and points to a better tool. Every comparison page has a date stamp at the top showing when its pricing and feature claims were last checked.
I don't accept payment, sponsorship, or affiliate fees from any tool listed in a comparison or alternatives page. There are no affiliate links on this site.
If anything stated about another product is wrong, outdated, or unfair, I want to fix it. The fastest path is opening a GitHub issue at github.com/thevrus/MarkLayer/issues with the URL and the specific claim that needs updating. Corrections typically ship within a few days. If a competitor has changed pricing or shipped a feature that closes a gap I called out, that's the kind of update I want to see and apply.
GitHub Issues for product feedback or comparison-page corrections. Email at rusinvadym@gmail.com for everything else.