Microsoft rebuilds Teams to be 2x faster, paving way for Copilot

If you use Microsoft Teams at work, you already know the daily pain: high memory usage, spinning laptop fans, and clunky account switching.

Microsoft just rolled out a public preview of a completely rebuilt Teams desktop client, and the performance claims are massive. According to Sumi Singh, CVP of engineering for Teams, the new client runs twice as fast while using 50 percent fewer resources.

Installing the app is three times faster, launching it and joining meetings is twice as fast, and memory footprint has been cut in half alongside a 70 percent drop in disk space usage.

Ditching Electron for raw speed

To make this leap, Microsoft essentially scrapped the app's foundational architecture and rebuilt it from scratch.

The old Teams was notorious for running on top of Electron while awkwardly juggling two different JavaScript frameworks: legacy AngularJS and React. That setup forced the app to carry unnecessary bloat just to render text and video.

The new client completely abandons Electron in favor of Microsoft's Edge WebView2 runtime, paired with a full transition to React and Fluent design. By sharing underlying resources with the Edge engine, Teams no longer hoards standalone system assets.

According to Microsoft, the overhaul touches everything from data storage and network layers to the entire video rendering pipeline.

Practical tweaks and an AI runway

The visual overhaul aligns Teams with Windows 11 using native Mica translucency, switching canvas tones from gray to white, and toning down the purple theme. Dark mode now toggles automatically.

Quality-of-life updates are equally noticeable. Workers juggling multiple corporate tenants can now monitor all accounts and notifications from a single dropdown without logging out.

The meeting experience also gained automated hand-lowering after speaking, Loop component embedding inside Whiteboard, and AI video framing filters.

Crucially, Microsoft engineered this lighter base to support its upcoming Copilot assistant. The team noted that deploying Copilot requires rapid testing and continuous model feedback, which the sluggish legacy framework simply could not sustain.

For now, the preview is restricted to commercial Windows users via a toggle switch, with Mac, education, and web versions slated for later. Third-party app integrations, call queues, and breakout rooms are currently missing from the preview build.

Why it matters

For millions of daily corporate users, cutting memory consumption in half while doubling load speeds provides immediate relief, especially on mid-tier work laptops. That said, because third-party enterprise integrations and breakout rooms are absent in this build, we think teams relying on complex workflows should treat this as a test drive rather than an immediate full migration.

Across the industry, this marks a significant shift away from traditional Electron wrappers for mission-critical enterprise software. Slack and Zoom will face renewed pressure to prove their native desktop efficiency.

We think Microsoft made a smart strategic calculation here. Packing Copilot and complex generative tools into a client that already choked on simple video calls would have been a disaster. By doing the hard, unglamorous engineering work of rebuilding the foundation first, Microsoft ensures that when AI features roll out widely, users will actually have the headroom to run them.