Valentin Kao
Senior Software Engineer and AWS Solutions Architect based in Taiwan, originally from Toulouse, France. I build production systems from scratch: serverless backends, cloud infrastructure, and AI-powered applications.
I've built an IoT platform that scaled to 2M devices at 500+ req/s, a FinTech app backend serving handling real money transactions, and production AI systems including voice interview agents and automated data extraction.
I work as a freelance engineer and consultant. If you need someone to own your backend, infrastructure, and AI stack end-to-end, from architecture to production, that's what I do.
When I'm not building software, I'm recharging with Muay Thai, lifting, or running.
What I do
Cloud & serverless backends: AWS Lambda, DynamoDB, API Gateway, ECS Fargate, SQS/SNS, EventBridge, Step Functions
AI in production: OpenAI, Claude, AWS Bedrock, Google Gemini, LiveKit voice agents, RAG pipelines, multi-LLM routing
Infrastructure as Code: Terraform + Terragrunt, AWS CDK, SAM, CloudFormation
Backend: Node.js, NestJS, FastAPI, Python, TypeScript, WebSocket APIs, event-driven systems
Frontend & mobile: React, Next.js, React Native + Expo, Tailwind CSS
Data & integrations: PostgreSQL, DynamoDB, Kinesis, IoT (LoRaWAN, Sigfox, BLE), Stripe, third-party APIs
Experience
FinTech platforms (Cagn'Up, DealBreaker). NestJS, ECS Fargate, Terraform
Multi-tenant IoT SaaS with Bedrock AI. Led team of 4, AWS CDK, 31 nested stacks
IoT middleware for 2M devices. Built and led team of 7, ISO 27001 certified
AI code review SaaS. Multi-LLM routing, 40% cost reduction vs. single-provider
Education
Available for freelance projects and consulting. Reach out, or check out my work.
This is a collection of ideas, stories, tutorials, and whatever come to my mind. Better sharing them than keeping them into a Notion privately.
Feb 23, 2026
Your AGENTS.md Is Probably Making Your AI Agent Worse
Feb 19, 2026
Your AI System's Biggest Cost Driver Isn't the Model
Feb 18, 2026
I Scaled an IoT Platform to 2M Devices on Lambda - Today I'd Change One Thing
Feb 17, 2026
AWS Quietly Removed the Biggest Serverless Constraint
Feb 12, 2026
If Your Infrastructure Isn't Defined in Code, It Doesn't Exist
Feb 10, 2026
Claude Opus 4.6 Just Landed in Bedrock. Can Your AI Product Actually Use It?
Nov 10, 2023
Staying in Taiwan with a Taiwan Gold Card
Oct 23, 2023
Serverless Computing for a Modern-Day Development
Oct 2, 2023
From being Software Engineer into leading a team of 6 engineers