Larry Xiong
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ENGINEERING NOTES

Notes from building software.

Practical lessons and technical explorations across full-stack development, backend systems, and applied AI.

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Backend EngineeringFull-StackBackground Jobs

Faster Uploads with Background Processing

How background workers can improve document upload responsiveness, with Redis, Celery, reliable task handling, and clear processing status.

· ~7 min read
A laptop displaying an analytics dashboard on a reflective table
FintechBackend EngineeringProduct Delivery

Reducing Friction in Financial Onboarding

How better workflow design, reliable third-party integrations, and clear verification states helped reduce signup time by 60% and manual review work by 40%.

· ~8 min read
A computer monitor displaying analytics charts
RAGEvaluation

Evaluate RAG at the Retrieval Boundary

How to evaluate retrieval quality, identify missing evidence, and build more reliable RAG systems using practical metrics and structured testing.

· ~10 min read
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RetrievalSearch Engineering

Hybrid Search: Give Exact Matches and Meaning a Vote

Why combining keyword search and semantic retrieval can improve RAG systems, how reciprocal rank fusion works, and what to measure before adding more complexity.

· ~11 min read
A close-up photograph of a computer circuit board
LLMsContext Engineering

A Larger Context Window Is Not an Evidence Strategy

Why longer context windows don't always produce better answers, and how to select, organize, and evaluate evidence for reliable LLM applications.

· ~10 min read
Eyeglasses in front of computer screens displaying source code
AI AgentsBackend Engineering

Tool-Calling Agents Need Explicit Execution Boundaries

How to build reliable AI agents with clear tool contracts, secure execution, controlled retries, and practical safeguards for real-world operations.

· ~11 min read