# Lee daeyun (이대윤) | Production AI Agent and Realtime Backend Engineering Notes
> This site documents production AI agent architecture, realtime systems, and operational design decisions with concrete implementation evidence.

Lee daeyun is an Agent Engineer / Game Server Developer focused on systems that stay reliable under real user traffic.
The core signal of this blog is operational quality: state modeling, failure recovery, observability, and latency-aware backend design.
Most writing is based on shipped work across voice/realtime agents, workflow orchestration, telemetry pipelines, and payment/permission consistency.

## Core Pages
- [Home](https://dleodbs.xyz/) - Primary entry point with recent engineering notes and current focus.
- [About](https://dleodbs.xyz/about/) - Career timeline, problem-solving principles, and topic priorities for 2026.
- [Topic Tags](https://dleodbs.xyz/tags/) - Cross-cutting topic index for architecture and production notes.
- [Articles Index](https://dleodbs.xyz/publish/) - Full list of technical posts with dates and summaries.
- [Realtime Voice Agent Production Notes](https://dleodbs.xyz/publish/realtime-voice-agent-production-notes/) - Real deployment constraints and stabilization patterns for OpenAI Realtime-based systems.
- [Long-term Context Memory Architecture](https://dleodbs.xyz/publish/long-term-context-memory-architecture/) - Storage/retrieval separation strategy for persistent agent memory.
- [Subscription Payments Webhook State Machine](https://dleodbs.xyz/publish/subscription-payments-webhook-state-machine/) - Billing state consistency model using webhooks and authorization sync.
- [LangGraph Agent Orchestration in Production](https://dleodbs.xyz/publish/langgraph-agent-orchestration-in-production/) - State-transition orchestration with checkpoints and retry boundaries.

## Evidence
- [Infra Deploy Run: Observability-first Delivery](https://dleodbs.xyz/publish/infra-deploy-run-observability-first/) - How deployment structure reduced incident surface area.
- [Autonomous Robot Realtime Streaming Optimization](https://dleodbs.xyz/publish/autonomous-robot-realtime-video-streaming-optimization/) - Low-latency streaming and control-path tradeoff handling.
- [AWS IoT Firehose Elasticsearch Pipeline](https://dleodbs.xyz/publish/aws-iot-firehose-elasticsearch-pipeline/) - Telemetry ingestion and searchable operations pipeline.
- [Discord Interaction State Modeling](https://dleodbs.xyz/publish/discord-interaction-state-modeling/) - Multi-step interaction state design for reliable bot workflows.
- [Agent Coding Has Hard Boundaries](https://dleodbs.xyz/publish/agent-coding-has-hard-boundaries/) - Failure modes and control boundaries in agent-assisted development.
- [Resume Is a Hypothesis](https://dleodbs.xyz/publish/resume-is-a-hypothesis/) - Why this blog is treated as evidence instead of self-claims.

## Optional
- [LLMs Full Briefing](https://dleodbs.xyz/llms-full.txt) - Expanded topic map and retrieval-oriented links.
- [RSS Feed](https://dleodbs.xyz/index.xml) - Machine-friendly stream of newly published posts.
- [Sitemap](https://dleodbs.xyz/sitemap.xml) - URL discovery list for crawlers.
- [GitHub](https://github.com/dleodbs) - Source-level work and implementation artifacts.
- [LinkedIn](https://www.linkedin.com/in/lee-daeyun) - Career identity and professional timeline.