Building the JSON lines for calltraces for logs in the following format: [start-timestamp] [end-timestamp] [trace] [service-name] [caller-span]->[span]
go build cmd/logtracer/logtracer.go
asomeprogram | logtracer
docker run --rm -v $PWD:/data asciinema/asciicast2gif -s 2 -t solarized-dark demo.cast demo.gif