2025 / REAL-TIME SYSTEM
CoreWire.
What happens when multiple people edit the same state at once?
A collaborative code workspace built for low-latency technical interviews, where every keystroke is shared state.
Personal project · real-time collaboration
Node.js · Express · WebSockets · MongoDB · React
THE USEFUL OUTCOME
What this makes possible.
A shared code workspace for technical interviews, so participants can follow edits directly.
THE ENGINEERING SIGNAL
What the work demonstrates.
Resolved an update feedback loop by distinguishing local edits from remote changes.
Why I Built It
A technical interview exposed the friction of coding in a text editor while screen-sharing. I wanted a shared workspace where an interviewer could follow the code directly.
The Problem
Testing the editor with a friend revealed flickering, even when we were not typing simultaneously. Shared updates were feeding back into the same event flow.
The Interesting Failure
A remote update was treated as a new local edit and broadcast again. That created a feedback loop: the same change kept travelling between clients.
The Decision
I distinguished local edits from remotely applied changes so received updates would not be broadcast again. I also tied authenticated user IDs to socket sessions to address session spoofing.
What Changed
The flickering disappeared in my testing after separating local and remote state changes. This made the update flow easier to reason about.
What I'D Fix Next
Validate the workspace with real users and measure its behaviour under concurrent load. The project has not yet demonstrated production scale.
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