Technology Stack

This document centralizes all technology decisions for the AICO system. It provides a comprehensive overview of the technologies selected for each layer of the architecture.

Interface Layer

Technology	Purpose	Justification
Flutter	Cross-platform UI framework	Single codebase for desktop/mobile, high performance, rich widget library
WebView	3D avatar rendering	Embeds web-based avatar technologies within Flutter
Three.js	3D graphics library	Industry standard for web-based 3D rendering
Ready Player Me	Avatar creation	Customizable avatars with built-in animation support
TalkingHead.js	Lip-sync and expressions	Real-time lip-sync and facial expression capabilities
JavaScript Bridge	Flutter-WebView communication	Bidirectional communication between Flutter and web avatar

AI/ML Layer

Technology	Purpose	Justification
Llama.cpp	Local LLM inference	Efficient quantized models, cross-platform support
Ollama	LLM management	Simplified model management and API
Mistral	Base LLM architecture	Strong performance in quantized form
LangChain/LangGraph	Agent orchestration	Graph-based workflow for complex agent behaviors
CrewAI/Autogen	Multi-agent coordination	Enables collaborative agent behaviors
RND	Curiosity algorithm	Random Network Distillation for intrinsic motivation
ICM	Curiosity algorithm	Intrinsic Curiosity Module for prediction-based rewards
HER	Goal-conditioned learning	Hindsight Experience Replay for learning from failures
GCPO	Goal-conditioned learning	Goal-Conditioned Policy Optimization for on-policy learning
MCTS	Planning system	Monte Carlo Tree Search for decision making
Behavior Trees	Action modeling	Goal-oriented behavior modeling and execution
AppraisalCloudPCT	Emotion simulation	Component Process Model for sophisticated emotion generation
ONNX Runtime	Model inference	Cross-platform inference optimization
OpenVINO	Edge inference	Intel optimization for edge devices
Whisper.cpp	Speech-to-text	Efficient local speech recognition
Coqui/Piper	Text-to-speech	Local high-quality voice synthesis

Data & Storage Layer

AICO employs a specialized multi-database architecture optimized for local-first operation. See Data Layer for comprehensive details.

Technology	Purpose	Justification
libSQL	Primary storage	Modern SQLite fork with encryption, improved concurrency, and vector extensions
DuckDB	Analytical engine	Columnar storage for efficient OLAP workloads and complex analytics
ChromaDB	Vector database	Embedded vector storage with document metadata and similarity search
RocksDB	Key-value store (optional)	Ultra-fast access for performance-critical paths and caching
Sentence Transformers	Embedding generation	Efficient text embedding models for semantic understanding
P2P Sync Protocol	Federated device sync	Custom protocol for secure device-to-device synchronization

Communication Layer

Technology	Purpose	Justification
ZeroMQ	Internal message bus	Lightweight, embedded pub/sub messaging for all core modules
FastAPI	API framework	Modern, fast Python web framework powering the service gateway
REST API	UI/adapter protocol	Standard HTTP API for commands, queries, and configuration
WebSocket API	UI/adapter protocol	Real-time, bidirectional communication for events and notifications
Protocol Buffers	Message format	High-performance binary serialization with strong typing and cross-platform support
protoc	Code generation	Automatic code generation for multiple languages (Python, Dart)

Security & Privacy Layer

Technology	Purpose	Justification
gocryptfs	Filesystem-level encryption	Transparent encryption for all database files with zero functionality loss
AES-256-GCM	Authenticated encryption	Industry standard encryption with integrity verification
Argon2id	Key derivation	Industry-leading memory-hard KDF, winner of Password Hashing Competition
Python-Cryptography	Cryptographic library	Comprehensive, well-maintained cryptographic primitives with Argon2id support
Platform Key Storage	Secure key management	OS-native secure storage (Keychain, Credential Manager, Secret Service)
Homomorphic Encryption	Privacy-preserving computation	Compute on encrypted data
Differential Privacy	Statistical privacy	Privacy-preserving analytics
Zero-Knowledge Proofs	Authentication	Verify without revealing data
Secure Multi-party Computation	Collaborative learning	Learn without sharing raw data

Deployment & Distribution Layer

Technology	Purpose	Justification
Docker/Podman	Containerization	Isolated, reproducible environments
Alpine Linux	Base images	Minimal footprint for containers
Electron	Desktop packaging	Cross-platform desktop application packaging
Delta Updates	Efficient updates	Bandwidth-efficient update mechanism
Cryptographic Signatures	Update verification	Ensures update authenticity

Development & Testing Layer

Technology	Purpose	Justification
Python	Core development	Primary language for AI components
Dart/Flutter	UI development	Cross-platform UI framework
JavaScript/TypeScript	Avatar development	Web technologies for avatar system
Pytest	Testing framework	Comprehensive Python testing
GitHub Actions	CI/CD	Automated testing and deployment
MkDocs	Documentation	Markdown-based documentation system
Material for MkDocs	Documentation theme	Clean, responsive documentation UI

Command-Line Interface (CLI)

Technology	Purpose	Justification
Typer	CLI framework	Modern, maintainable, autocompleting command trees
Rich	Output formatting	Beautiful, readable, Unicode-rich CLI output
PyInstaller	Packaging	Creates single-file, dependency-free, cross-platform executables
Platformdirs	Config management	Cross-platform config/cache path handling
ZeroMQ (pyzmq)	Message bus integration	Direct backend communication for admin/automation
Requests/httpx	API communication	Fast, reliable backend service integration

• CLI is cross-platform (Windows, macOS, Linux) and offers a top-tier, professional UX.
• Executable is universal, not dependent on Python/.venv on the target system.
• CLI reuses backend modules for DRY and maintainable architecture.

Monitoring & Instrumentation Layer

Technology	Purpose	Justification
OpenTelemetry	Telemetry standard	Unified API for metrics, logs, and traces with minimal overhead
Structlog	Structured logging	Python library for consistent, structured log output
libSQL	Log & telemetry storage	Reuses existing database with time-series optimized tables
Pydantic	Schema validation	Efficient validation of telemetry and audit records
Grafana	Visualization (dev only)	Optional local dashboard for development and debugging
Loki	Log aggregation (dev only)	Lightweight log aggregation for development environments

Module-Specific Technologies

Personality Simulation

Technology	Purpose	Justification
TraitEmergence	Personality architecture	Multi-dimensional trait-based modeling
Big Five & HEXACO	Trait models	Comprehensive personality representation

Emotion Simulation

Technology	Purpose	Justification
AppraisalCloudPCT	Emotion architecture	Advanced Component Process Model variant
4-Stage Appraisal	Emotion generation	Cognitive appraisal process (Relevance → Implication → Coping → Normative)

Autonomous Agency

Technology	Purpose	Justification
MCTS	Decision making	Monte Carlo Tree Search for planning
Behavior Trees	Action execution	Structured behavior representation
RND/ICM	Curiosity algorithms	Intrinsic motivation for exploration
HER/GCPO	Goal learning	Goal-conditioned reinforcement learning

Avatar System

Technology	Purpose	Justification
Three.js	3D rendering	Web-based 3D graphics
Ready Player Me	Avatar models	Customizable 3D avatars
TalkingHead.js	Facial animation	Real-time lip-sync and expressions
WebView	Integration	Embedding web technologies in Flutter