Juno

A production-grade, multimodal AI platform and native client ecosystem.

Streaming Chat · Deep Research · Durable Memory · Canvas Artifacts · Model Context Protocol (MCP) · Realtime Voice Relay · Cloud & Device Code Agents · Native macOS & iOS Apps

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Overview

What is Juno?

Juno is a modern, full-stack, multimodal AI platform designed for serious everyday work. It combines a high-performance web experience with dedicated native desktop (macOS) and mobile (iOS) applications, backed by a unified synchronization engine and strict security architecture.

Why does Juno exist?

Most open-source AI chat frontends are either lightweight web wrappers around single provider APIs or monolithic prototypes lacking production security, multi-device synchronization, or deep agentic workflows. Proprietary platforms, conversely, vendor-lock users into closed ecosystems with opaque data practices.

Juno fills this gap by delivering:

1. Model & Provider Interoperability: Zero vendor lock-in across OpenAI, Anthropic, Google Gemini, xAI Grok, Mistral, Meta Llama, DeepSeek, Perplexity, Cohere, and local/custom endpoints.
2. First-Class Native Experience: Native Swift applications for macOS and iOS that share contracts, tokens, and offline/online state synchronization with the web core.
3. True Agentic Capabilities: Unified tool execution, Model Context Protocol (MCP) connectors, autonomous "Code" agent sessions, and persistent agentic teammates with goals and memory.
4. Defense-in-Depth Security: Nonce-based CSP, cryptographic encryption-at-rest for user conversations, strict ownership query enforcement, and action-bound approval receipts.

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Key Capabilities

• Unified Multi-Provider Generation: Seamlessly stream turns, visible thinking/reasoning blocks, and tool executions across 14+ model providers with automatic failover and reasoning effort ladders.
• Deep Research & Canvas Artifacts: Interactive document workspaces, live code previews (React, Tailwind, HTML, SVG, Mermaid), version history, and full-screen reading modes.
• Durable Memory & Personalization: Long-term memory distillation with encrypted summary profiles and user-controlled forgetting.
• Model Context Protocol (MCP) & Connectors: Dynamic discovery, OAuth registration, and tool calling across local and remote MCP servers (Linear, GitHub, Notion, Slack, Google Workspace, Apple ecosystem).
• Multimodal Realtime Voice: Low-latency audio streaming relay (relay/) supporting duplex speech-to-speech, read-aloud synthesis, and continuous dictation.
• Code & Work Sessions: Sandboxed cloud execution environments (runner/) and device-bridged agents capable of inspecting file systems, running bash commands, and checking execution outcomes.
• Native Ecosystem: Full-featured native clients for macOS (Menu Bar, Global Hotkey, Spotlight-like quick access) and iOS (Dynamic Island, Live Activities, Lock Screen widgets).

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Architecture at a Glance

┌────────────────────────────────────────────────────────────────────────┐
│                              Clients                                   │
│   Web (Next.js 15)   │   macOS (Swift/AppKit)   │   iOS (Swift/SwiftUI) │
└───────────┬──────────────────────┬──────────────────────┬──────────────┘
            │                      │                      │
            ▼                      ▼                      ▼
┌────────────────────────────────────────────────────────────────────────┐
│                        Juno Backend Core                               │
│  • Next.js App Router (Modular API & Route Handlers)                   │
│  • NextAuth v5 + TOTP 2FA + Immediate Session Revocation               │
│  • Ownership Query Guard (Mandatory User-Scoping)                      │
│  • Encrypted Transcript & Credential Storage (AES-256-GCM)             │
└───────────┬──────────────────────┬──────────────────────┬──────────────┘
            │                      │                      │
    ┌───────┴────────┐     ┌───────┴────────┐     ┌───────┴────────┐
    ▼                ▼     ▼                ▼     ▼                ▼
┌──────────────┐ ┌──────────────┐ ┌──────────────┐ ┌──────────────┐
│  PostgreSQL  │ │  S3 Storage  │ │ Voice Relay  │ │ Cloud Runner │
│   (Prisma    │ │ (Attachments,│ │  (WebSocket  │ │ (Agent Core, │
│  Migrations) │ │  Artifacts)  │ │   Service)   │ │  Sandboxed)  │
└──────────────┘ └──────────────┘ └──────────────┘ └──────────────┘

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Security Model

Juno implements defense-in-depth controls audited for production workloads:

• Encryption at Rest: Transcripts (Message.content), visible thinking (reasoning), tool call activities, long-term memory summaries, and OAuth connector tokens are encrypted using rotatable AES-256-GCM keyrings (src/lib/message-crypto.ts, src/lib/crypto.ts).
• Database Ownership Enforcement: The Prisma data access layer (src/lib/db.ts) automatically rejects unscoped queries on user-owned tables, verified by static call-site auditing (tests/ownership-guard-callsites.test.ts).
• Action-Bound Approval Receipts: External mutations and sensitive connector invocations require cryptographic SHA-256 approval receipts bound to user, session, and exact arguments.
• Origin & CSRF Protection: Strict same-origin validation on cookie-authenticated mutations; bearer authentication contract enforced for native clients.
• Automated Security Pipelines: CodeQL static analysis, GitHub Secret Scanning push protection, and Dependabot supply chain updates.

For detailed disclosure guidelines, see SECURITY.md.

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Quick Start

Prerequisites

• Node.js 20+ (Node 24 recommended)
• PostgreSQL 15+
• npm 10+

Installation

# 1. Clone the repository
git clone https://github.com/LiamMagnier/juno.git
cd juno

# 2. Install dependencies (triggers Prisma client generation)
npm install

# 3. Configure environment variables
cp .env.example .env.local
# Edit .env.local with your DATABASE_URL, AUTH_SECRET, and API keys.

# 4. Run database migrations
npx prisma migrate dev

# 5. Extract i18n catalogs and start the development server
npm run dev

Visit http://localhost:3000 to create an account and begin.

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Development & Quality Gates

Juno enforces strict quality and contract integrity gates across both web and native targets:

# Prepare the state CI tests in: Node 24 check, UI translation strings,
# runner installs and the agent-core build
npm run test:prepare

# Run full project typecheck
npm run typecheck

# Run linter
npm run lint

# Run automated test suites
npm test

# Verify Swift-TypeScript contract sync
npm run capabilities:check
npm run work:contract:check

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Self-Hosting & Deployment

Juno can be deployed in two primary configurations:

1. Standalone Production VM (Recommended): Nginx reverse proxy routing to Next.js (App Router), the standalone realtime voice relay (relay/), and the background scheduler under PM2. Complete deployment guides are provided in:
   • Oracle Cloud Always-Free Setup Guide
   • Google Cloud Platform Setup Guide
2. Hybrid Cloud: Edge/Serverless web frontend with /api/* and WebSocket traffic routed to a dedicated backend instance.

See docs/JUNO.md §20 for complete operational runbooks.

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Contributing

We welcome contributions from the community! Please review our:

• Contributing Guide for local setup, commit conventions, and testing requirements.
• Code of Conduct for community standards.
• Project Governance for maintainer roles and decision-making processes.

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License & Third-Party Notices

Juno is open-source software licensed under the Apache License, Version 2.0.

Third-party dependencies, vendored components (runner/agent-core/), typography, and provider trademark notices are documented in NOTICE.