1. Ground VM

Rent a small Linux VM ($0.01–$0.03/h, Python 3.9+, open TCP port 8444) close to where the satellite downlinks to fiber. Check curl ipinfo.io on raw cabin Wi-Fi first to see the egress country/ASN:

• Emirates / Middle East & European flights (Inmarsat GX / SITA AS206433): Amsterdam, Frankfurt, or Hetzner EU (downlink lands in the Netherlands).
• North America: us-east or us-west.
• Asia-Pacific: Singapore or Tokyo.

Pause UDP VPNs (Tailscale/WireGuard) inflight—blocked UDP retry traffic competes for cabin airtime.

2. Run

With a coding agent:

Spin up a temporary Ubuntu VM near my current satellite egress IP, start https://github.com/Th0rgal/satmux on port 8444, connect the local 12-carrier client, enable bin/satmux-macos on, and run bin/satmux-bench.

Or manually:

# 1. Laptop: generate PSK
git clone https://github.com/Th0rgal/satmux.git && cd satmux
openssl rand -hex 32 > mux.psk && chmod 600 mux.psk

# 2. Ground VM: start server
scp satmux.py mux.psk root@<SERVER_IP>:/root/
ssh root@<SERVER_IP> 'nohup env SATMUX_PSK=$(cat /root/mux.psk) python3 /root/satmux.py server --port 8444 >/var/log/satmux.log 2>&1 &'

# 3. Laptop: start client + enable macOS / git / gh routing
SATMUX_PSK=$(cat mux.psk) python3 satmux.py client --host <SERVER_IP> --port 8444 --carriers 12 &
./bin/satmux-macos on <SERVER_IP>

Benchmark or run parallel range downloads:

./bin/satmux-bench
./bin/satmux-get https://example.com/archive.tar.gz

3. Teardown after landing

./bin/satmux-macos off

Restores macOS Wi-Fi proxy settings, ~/.gitconfig, gh http_unix_socket, and launchctl env vars, then destroy the temporary VM.