Honorable mention
Mumble is an open-source, low-latency, high quality voice chat software.
definitive-opensource
Communication & Collaboration
Open protocols and self-hostable stacks for teams that outgrow closed silos—matrix, team chat, and secure messaging. Multi-protocol desktops like Pidgin still matter where IRC, XMPP, and plugin ecosystems overlap.
Tools in this category (19)
Honorable mention
bluetooth mesh chat, IRC vibes
definitive-opensource
Honorable mention
Legcord is a custom client designed to enhance your Discord experience while keeping everything lightweight.
definitive-opensource
Matrix client for federated, E2EE-capable real-time communication.
chatmatrixfederatione2ee
E2EE messenger with conservative security posture and broad adoption.
messaginge2eemobile
Team messaging platform with strong self-hosted enterprise adoption.
team-chatenterpriseself-hosted
Also strong
Team chat platform with channels, threads, video, and broad integration marketplace.
chatteamself-hosted
Also strong
Thread-first team chat combining email-like topics with real-time messaging.
chatthreadsself-hosted
Honorable mention
Messenger using email as transport—chat over your existing IMAP/SMTP accounts.
chatemailprivacydecentralized
Open standard for decentralized, encrypted real-time communication; reference server Synapse.
federationchate2ee
Honorable mention
Open programmable telephony APIs (Twilio-class narrative).
voipcpaasapi
Secure WebRTC video conferences embeddable or standalone.
webrtcvideomeetings
Honorable mention
E2E-encrypted team chat, calls, and file sharing.
chate2eeteams
Also strong
Decentralized messaging with privacy-first routing.
messagingprivacydecentralized
Honorable mention
Lightweight Matrix homeserver in Rust.
matrixrustfederation
Honorable mention
Real-time XMPP server for chat and presence.
xmppchatserver
Honorable mention
Groupware server for calendars, contacts, and email integration.
groupwarecaldavemail
Honorable mention
Multi-protocol chat client with libpurple plugins for XMPP, IRC, and various legacy networks.
chatxmppirclibpurple
Honorable mention
Telegram Desktop messaging app
definitive-opensource