Schleuder

Self-hostedOpen sourceCommunication

GPG-enabled mailing list manager with resending-capabilities.

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Federated microblogging server.

Self-hostedOpen sourceCommunication

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Advanced forum / community solution based on Ruby and JS.

Self-hostedOpen sourceCommunication

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Communications platform that puts data protection first (alternative to Gitter.im and Slack).

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Platform for secure collaboration across the entire software development lifecycle, can be integrated with Gitlab (alternative to Slack).

Self-hostedFreeCommunication

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