Serenity

Decentralized Application

End-to-end encrypted, offline-first collaborative notes app using CRDTs (secsync architecture); relay never sees plaintext

Community

Links

Visit Community

Details

License

Open source client (github.com/serenity-kit); secsync library open source

Dev Status 🟢 Active

Dev Status Detail

Released (active, small-team; secsync beta)

Owner

Nik Graf / Naisho GmbH (serenity-kit)

Country

Austria

Start Year 2019

Stack

TypeScript + React Native

Funding

NGI Assure (via NLnet, grant for secsync Aug 2021 — Aug 2024)

Last Investigated Mar 9, 2026

Use Case Domains

Communication

Group Formation & Governance

Affordances

Consent-based audiences

Composable groups

Decentralized Application Attributes

Origins

E2E encrypted notes; inspired by Signal/Matrix encryption applied to collaborative documents

Database

CRDTs (Yjs via secsync; encrypted snapshots + updates)

Query Language

N/A

Data Formats

Custom (encrypted CRDT snapshots + updates; secsync protocol)

Collaborative Live Editing

Yes (CRDT-based, E2EE via secsync; cursor awareness)

Rich Text Editing

Yes

Mobile Support

Yes (iOS native; Android in development)

Web Support

Yes

Native Apps

Yes (macOS via React Native)

Terms

Self-hosting + Freemium SaaS

Funds

NGI Assure grant (undisclosed amount; run by Nikolaus Graf / Naisho GmbH)

Based On

secsync (E2EE CRDT relay architecture) built on Yjs

Use Case Category

Note-taking + Collaboration

User Interface Type

Document-centric

Offline Capabilities

Full functionality offline (local-first; secsync designed for offline-first)

Collaboration Features

Real-time editing (E2EE), sharing via contacts, cursor awareness

Data Portability

Partial (CRDT document data portable; not yet implemented in prototype)

Integration Ecosystem

N/A

Web2 Data Export

N/A

Prosocial Coherence

N/A

Economic Flows

N/A

Governance & Decision Making

Company-controlled (Naisho GmbH, small team)

Media / Publishing

Knowledge Management

Sensemaking

Project Management

Data Sovereignty

Full (E2E encrypted on device; relay never sees plaintext; user-controlled keys)