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You can create, sign and distribute plugins with dependent technologies that are closed source or commercially backed, by entering into a Commercial Plugin Subscription with Grafana Labs.
Commercial Plugins are published on the official Grafana catalog, and are available to the Grafana community.
Checkmk was not considered a Community Plugin, even though the plugin also supports our open source edition as well. Therefore we have to enter a “Commercial Plugin Subscription with Grafana Labs”. We have been in discussions since July 2021 with Grafana and thanks to @marcel.arentz’s work and the help of our large customers, we are hopefully on the final steps to close this deal.