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A whiteboard for remote technical interviews — no candidate signup

Send one URL. Candidate opens it, you both draw on the same canvas, ~100 ms latency. No "create a Miro account first" friction, no SSO redirects, no permissions to grant. System-design diagrams, Mermaid sequence flows, freehand boxes — all in the browser.

Open a board for your next interview →

Why hiring managers pick cnvs.app for whiteboard rounds

Zero candidate friction. Most whiteboarding tools require signup. That eats 2–3 minutes of an already-tight interview and signals "we don't respect your time".
Both sides see the same thing. Real-time WebSocket sync, ~100 ms. The candidate's stroke appears on your screen instantly — and vice versa.
System design with Mermaid. Type a Mermaid flowchart or sequence diagram in a text node and it renders live. Cleaner than freehand for big architecture sketches.
Optional lock. Lock the board (mode: write) so only people with the 6-char key can edit. Public view still works for shadow interviewers.
Save for evaluation. Print / PDF export with the board URL watermarked, drop into the candidate scorecard.
Privacy. Boards self-purge after 30 days. No AI training on interview content. Compliant with most "no third-party data" policies.

How to run an interview whiteboard round

Before the call, open cnvs.app. Copy the URL.
(Optional) Lock the board for write — only people with the 6-char key can edit. Share the key separately.
Paste the URL into the call invite or chat at the start of the round.
Pose the problem — "Design a URL shortener that handles 10k QPS". Sketch together.
Encourage Mermaid for system-design boxes. The candidate types a flowchart in plain text and it renders.
Export to PDF when done.

What to draw

System design

Service boxes, DBs, queues, arrows for data flow. Use Mermaid C4 for cleaner architecture diagrams.

Sequence diagrams

Mermaid sequenceDiagram in a text node — way cleaner than freehand for showing request flows.

Data structure walkthroughs

Linked list nodes, tree levels, graph traversals — draw the state at each step, undo when wrong (Ctrl+Z).

Code on the canvas

Drop a Markdown-formatted text block with the function signature; sketch the algorithm around it.