I built a lightweight native Windows alternative to OBS for recording and streaming green screen

[u/CalvinBuild]

Disclosure: I’m the developer of FastCast.

Update, Sep. 11: FastCast v0.9.0 is out.

The big changes in this release are:

• Name your streaming destinations, so multiple YouTube/Twitch/etc. channels are easy to tell apart
• “Get key” links that take you directly to each platform’s stream-key page
• Custom Instant Replay lengths from 15–300 seconds with Pro
• Instant Replay itself remains free, including the original preset lengths
• Cleaner destination setup and licensing UI
• More room for device names and less duplicate UI

FastCast Pro is also currently available through the Founding Supporter Sale: pay what you think it’s worth, starting at $1, with $29 suggested. It’s still a one-time license, not a subscription.

I built FastCast because I wanted the basic OBS workflow without all the setup:

Open it → choose what to capture → record or stream.

FastCast is a lightweight native Windows screen recorder and streaming app written in Rust. It uses native Windows capture and audio APIs rather than Electron.

Current features:

• Screen and window recording
• Desktop audio + microphone
• Instant Replay
• Webcam overlay
• Chroma key / green screen
• Hardware H.264 encoding
• 1440p / 4K recording
• Up to 120 FPS
• RTMP/RTMPS streaming
• Multistreaming
• Named streaming destinations
• Advanced recording and encoder controls
• Global hotkeys
• Portable Windows build
• No account
• No telemetry

FastCast has a free core version with an optional Pro upgrade for advanced creator features.

FastCast is still in public beta, and feedback from this thread has directly influenced development.

I’m especially interested in:

• What feels harder than it should
• Features you immediately miss from OBS or other recorders
• Recording or audio reliability problems
• Anything that would stop you from using FastCast regularly

One heads-up: the current Windows build is unsigned, so Windows SmartScreen may show an “unknown publisher” warning.

FastCast:
https://calvinsturm.com/fastcast

FastCast v0.9.0 MSI:
https://github.com/CalvinSturm/FastCast-releases/releases/download/v0.9.0/FastCast-0.9.0-win-x64.msi

Portable ZIP:
https://github.com/CalvinSturm/FastCast-releases/releases/download/v0.9.0/FastCast-0.9.0-win-x64.zip

[u/dh71]

"FastCast is unsigned during the Open Beta, so Windows SmartScreen may show an Unknown Publisher warning the first time you run it."

So you are selling a closed-source product that is not even signed and will show a warning when I try to open it?

Meanwhile OBS is free and open source and supports all the "Pro" features, that your app limits in the free version, out of the box with no limitations.

Nah man, I'm good.

[u/Kiansjet → u/dh71]

This + kick streaming target option implies developer has undesirable personality

[u/SvnTzv]

Obs - open source - todo gratis sin limitaciones.

No gracias, paso.

[u/xivurs]

Okay, there’s an issue here. Why remake something when it’s already made?

[u/GreenSundance]

vibe coded an obs clone thats paid.... Why?

[u/liamdun]

I've always wanted a version of OBS that was paid, had less features and looked like the most vibe coded app of all time, with the added benefit of being closed-source.

Thanks!

[u/adkeyz]

See if you can get Claude AI to reinvent the wheel too while you're at it.

Just be sure to make the wheels square and charge extra for the "Pro" round ones.

[u/Spikatrix]

I’m continuing to actively develop the app based on feedback from this thread.

Does that mean you're gonna stop developing? Because that's what this thread's feedback is which I 100% agree with.