Eryx

Overview

Eryx is an AI assistant platform that provides intelligent conversations with real-time web search capabilities. Built with Next.js 16 and Bun runtime, it features a sophisticated context management system that handles long conversations efficiently through hierarchical summarization and structured memory.

Features

Intelligent Chat with Real-time Search

Web search via SearxNG integration when in web mode
AI-powered responses with configurable model selection (GPT-4.1, GPT-4o, GPT-5 series)
Resumable streaming for unreliable network conditions

Hierarchical Context Management

Layer 1: Recent 20 messages with full fidelity
Layer 2: LLM-generated conversation summaries stored in PostgreSQL
Layer 3: Structured key facts and topics extraction
Redis caching with 7-day TTL for summaries

MCP (Model Context Protocol) Integration

Connect multiple MCP servers as tools
OAuth-based authentication for MCP apps
Secure credential encryption with dedicated key management

Credit-based Billing

Polar integration for merchant-of-record payments
Multiple pricing tiers (Basic/Pro)
Real-time credit balance tracking
Usage-based model selection

Real-time Capabilities

WebSocket-based chat synchronization
Typing indicators and presence
Notification system
Customizable response styles

Architecture

┌─────────────────────────────────────────────────────────────────┐
│                           Client (Browser)                       │
└─────────────────────────────────────────────────────────────────┘
                                │
                                ▼
┌─────────────────────────────────────────────────────────────────┐
│                    Next.js App Router                            │
│  ┌─────────────┐  ┌─────────────┐  ┌─────────────────────────┐  │
│  │  API Routes │  │  Middleware │  │  Rate Limiting          │  │
│  │  (Server)   │  │  (Security) │  │  (Redis-based)          │  │
│  └─────────────┘  └─────────────┘  └─────────────────────────┘  │
└─────────────────────────────────────────────────────────────────┘
                                │
            ┌───────────────────┼───────────────────┐
            ▼                   ▼                   ▼
┌───────────────────┐ ┌───────────────────┐ ┌───────────────────┐
│   Services        │ │   AI Provider     │ │   External        │
│  (Business Logic) │ │   (OpenAI)        │ │   Services        │
│  - Chat Service   │ │                   │ │   - Polar         │
│  - Credit Service │ │                   │ │   - SearxNG       │
│  - RAG Service    │ │                   │ │   - MCP Servers   │
└────────┬──────────┘ └───────────────────┘ └───────────────────┘
         │
         ▼
┌───────────────────┐ ┌───────────────────┐
│   Redis           │ │   PostgreSQL       │
│   (Cache/PubSub)  │ │   (Prisma ORM)     │
└───────────────────┘ └───────────────────┘

Runtime: Bun (runs the Next.js server)

Tech Stack

Frontend: Next.js 16.2.4, React 19.2.5, TypeScript
Runtime: Bun
Database: PostgreSQL + Prisma ORM
Cache/PubSub: Redis (ioredis)
Auth: Stack Auth
AI: OpenAI via @ai-sdk/openai with custom provider mapping
Payments: Polar (Merchant of Record)
Search: SearxNG
Queue: BullMQ for async job processing
UI: shadcn/ui, Radix, Tailwind CSS

Key Technical Implementations

Resumable Streaming

Handles network interruptions gracefully by maintaining stream state in Redis. If a stream is interrupted, clients can resume from the last received position without losing context.

Hierarchical Context System

Instead of simple token truncation, the system uses LLM-generated summaries that preserve:

Conversation overview
Key topics discussed
Important facts and decisions

MCP Tool Integration

Users can connect MCP servers that expose tools. These tools are dynamically loaded and can execute code, query APIs, or perform other operations on behalf of the AI.