Lauren Wu

JetBrains AI Assistant generated code suggestions but displayed them in a separate panel, requiring developers to manually copy and compare changes. Only 14% of suggestions were accepted because the context-switch was too disruptive.

Built a custom inline diff renderer that overlays AI suggestions directly in the editor gutter using the IntelliJ PSI tree. Implemented smooth animated transitions, partial accept (line-by-line), and undo-as-a-unit. Used incremental rendering to handle large diffs without UI jank.

Suggestion acceptance rate jumped from 14% to 41%. Time-to-accept dropped from 8.2s to 2.1s. Feature shipped to 4.2M IntelliJ users and became the default AI interaction surface.

Third-party extensions crashed frequently in Codespaces due to differences between local VS Code and the remote container environment.

Designed a sandboxed extension host bridge that proxied file system and terminal access through a WebSocket layer, isolating extension state from the container.

Extension crash rate in Codespaces dropped from 12% to 1.8%. Enabled 340+ extensions to work without modification in the browser.

The github.dev web editor was sluggish on files over 5K lines, with noticeable lag on keystroke rendering and syntax highlighting.

Rewrote the syntax highlighting pipeline to use web workers and incremental tokenization. Implemented viewport-only rendering with virtual scrolling and lazy AST parsing.

Keystroke-to-render latency dropped from 45ms to 8ms on 10K-line files. Memory usage fell 35%. Received positive feedback in GitHub Universe developer survey.