[quote='798938021, erdeszbalazs, /thread/798938, /profile/erdeszbalazs'] Here is a simple command-line tool reproducing the issue: [/quote] I’m not surprised that code fails. You’re trying to encode the endpoint using a ‘vanilla’ JSONEncoder, and that has nowhere to store the Mach port rights. I’ve always envisaged implementing this using Codable structs. Pasted in at the end of this reply is an example of what I mean. When I built this with Xcode 26.0b7 and ran it on macOS 15.6.1, it printed this: will start anonymous listener did start anonymous listener will send check-in request, message: Hello Cruel World! 2025-09-02 09:09:13 +0000 did send check-in request will accept session request will accept check-in request, message: Hello Cruel World! 2025-09-02 09:09:13 +0000 did accept check-in request, clientID: 21BB21C9-40FE-4F85-B1AC-40E3ED0EA5B1 did receive check-in reply, id: 21BB21C9-40FE-4F85-B1AC-40E3ED0EA5B1 indicating that the reply made it back to the client. [quote='798938021, erdeszbalazs,
Topic:
App & System Services
SubTopic:
General
Tags: