Ok I’ve figured it out from trial and error: The framework's FNV-1a implementation multiplies before xoring, while most implementations online do the opposite. I just implemented it myself. For MurmurHash the implementation in this package will do https://github.com/daisuke-t-jp/MurmurHash-Swift The bits are stored “backwards” in the resulting data. In other words, write them in array order and then bit reverse every byte.

The problems I’ve originally reported as questions 2 through 4 appear to be fixed in the current beta. Any guidance about generating a correct bloom filter would be very much appreciated. The system is loading my filter properly now, but every URL gets “allowed”, presumably because my “bits” are incorrect.

The workaround of killing Settings before installing a new URL Filtering extension seems to work. However the system gets confused when you have multiple installed – if you switch one on from Settings they will all get enabled at once, which fails. I still haven’t managed to install "debug logging for Network Extension” but I will and submit some feedbacks. About the bloom filter tool, should we expect it in a reasonably short timeframe so we can start using it before these features ship? Cause if not I gotta go back to poking my code until I make it work right through sheer luck 😬

Still About 3): While my configuration is enabled, this line keeps being spammed in the logs: mapError unexpected error domain NEVPNConnectionErrorDomainPlugin code 7 Which appears to mean /** @const NEVPNConnectionErrorServerDead The VPN server is no longer functioning. */ case serverDead = 7 I don’t know if this is referring to the remote PIR server or just some locally running code. After I disable the configuration the following is spammed like 10 times before ceasing: mapError unexpected error domain NEVPNConnectionErrorDomainPlugin code 38 This one seems to be undocumented.

About 3): Digging further with Console, I saw this error message: NESMURLFilterSession[Wipr:...]: Failed to start with error: Error Domain=NSCocoaErrorDomain Code=4099 "The connection to service created from an endpoint was invalidated from this process." UserInfo={NSDebugDescription=The connection to service created from an endpoint was invalidated from this process.} Obviously no clue what this means 🥲 But it seems that the extensions with the NEURLFilterControlProvider cannot even be launched for some reason?