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A pulsar is a celestial object, thought to be a rapidly rotating neutron star, that emits regular pulses of radio waves and other electromagnetic radiation at rates of up to one thousand pulses per second.



Chatroulette uses this library in production as the base of the whole platform. However, this library is in active development so if you want to use it, do it at your own risk.


Check out the microsite.

Pulsar version

At the moment, we target Apache Pulsar 2.10.x.


If you have sbt installed, you don't have to worry about anything. Simply run sbt +test command in the project root to run the tests.

If you are a nix user, make sure you enter a Nix Shell by running nix-shell at the project's root.

sbt +test

Remember to first start Pulsar and initialize it with docker-compose

./docker-compose up -d


Working with schemas when using our Pulsar docker-compose configuration.

Get schema compatibility strategy:

$ docker-compose exec pulsar bin/pulsar-admin namespaces get-schema-compatibility-strategy public/default

Set schema compatibility strategy:

$ docker-compose exec pulsar bin/pulsar-admin namespaces set-schema-compatibility-strategy -c BACKWARD public/default