smalltalk-matrix/README.md

SmallTalk

SmallTalk is a minimal, modern, friends and family focused Android messenger. Heavily inspired by Whatsapp and Signal, powered by Matrix.

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Project mantra

• Tiny app size - currently 1.72mb~ when provided via app bundle.
• Focused on reliability and stability.
• Bare-bones feature set.

*Google play only with automatic crash reporting enabled

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Feature list

• Login with username/password (home servers must serve ${domain}.well-known/matrix/client)
• Combined Room and DM interface
• End to end encryption
• Message bubbles, supporting text, replies and edits
• Push notifications (DMs always notify, Rooms notify once)
• Importing of E2E room keys from Element clients

Planned

• Device verification (technically supported but has no UI)
• Invitations (technically supported but has no UI)
• Room history
• Message media
• Cross signing
• Google drive backups
• Markdown subset (bold, italic, blocks)
• Changing user name/avatar
• Room settings and information
• Exporting E2E room keys
• Local search
• Registration

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Technical details

• Built on Jetpack compose and kotlin multiplatform libraries ktor and sqldelight (although the project is not currently setup to be multiplatform until needed).
• Greenfield matrix SDK implementation, focus on separation, testability and parallelisation.
• Heavily optimised build script, clean cacheless builds are sub 10 seconds with a warmed up gradle daemon.
• Avoids code generation where possible in favour of build speed, this mainly means manual DI.
• A pure kotlin test harness to allow for critical flow assertions Smoke Tests, currently Linux x86-64 only.