Been a Kagi subscriber for a while, and am supportive of a more diverse browser ecosystem. However, I won't be using this browser as long as it is closed source. Honestly, the arguments made by the founder (I believe he's the founder anyway. I may be wrong) in the related feedback thread kind of soured me a little bit on Kagi. The arguments were essentially:

1. It's a lot of work to maintain an open source project accepting community contributions. Absolutely true, but that's not what's being asked for. Providing a tarball under an open source license doesn't add any significant work. 2. No one has asked for the Kagi backends to be open sourced, so why is the browser different? Obviously because I run the browser on my machine. Your backend runs on your machine. 3. We need to protect our IP. Then release it under a copyleft license. Or if you absolutely must, release your proprietary bit under a non-open source license. 4. You don't need the source because we send 0 telemetry, which you can verify using a network proxy. That's hardly the only thing to be worried about with a binary blob. Even if you kept the code completely closed source, by just releasing a tarball with the source under a proprietary license, I can build my own binary from source and eliminate this threat.