Startup · 0 → 1
A model-ready national dataset in 60 days
There was no existing platform team; I delivered the platform end to end, from architecture and code through deployment and daily operations.
Case context and my roleWork, writing, and a little campervan travel
Dewei Zhai
Freelance data platform architect & applied AI engineer · AWS · Azure · GCP
I help teams untangle complex data problems and build working solutions.
Hi, I'm Dewei. I work in tech and enjoy figuring out new things. Here you'll find things I've built and thoughts I've written down. Have a look around, and if something sparks a conversation, get in touch.
Contact me directlyProblems I have worked on
Read the complete CV →Three projects show how I approach data delivery in different teams, with the context, my role, and the results.
Large data organisation · evolve in place
Move hundreds of terabytes and cut feedback from hours to minutes
As a cloud administrator and data engineer, I supported the migration through AWS DMS Full Load + CDC and built the workflow automation and validation path.
Read the project retrospectiveLarger organisations · small core teams
Turn a 4–6 week dashboard path into 1–2 hours
In a roughly ten-person team without a Data Architect, I designed the platform path and acted as its de facto architecture lead.
Read the project retrospectiveRecent writing
All posts →
2026-09-03
Changing the Wheels While the Car Is Moving: Looking Back at My Oracle-to-Snowflake Migration
How automation reshaped an Oracle-to-Snowflake migration process, reduced disruption to ongoing development and manual drift, and helped the programme finish on time.
2026-09-01
Keep or Sweep: a structured way to remove redundancy
Use evidence, the deletion counterfactual, and retention duties to decide whether code, files, documents, or mechanisms should stay or go.
2026-08-26
A GDPR data workflow: from hourly polling to event-driven PII re-identification
How a GDPR-controlled PII workflow moved from always-on EMR and Aurora to S3 events, Step Functions, DynamoDB, and EMR Serverless—cutting typical latency from about two hours to 5–10 minutes and related AWS cost by about 90%.
2026-08-26
When an AI collaboration repo corrupts its own source of truth
I restructured a company AI-collaboration repo, clarified capability ownership and admission gates, and reduced Skill instructions by 51.7% while preserving behavior that genuinely matters.
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Work with me
Bring a specific data challenge for a one-off consultation or a project collaboration.
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Get in touch
Briefly describe the problem and what you would like to achieve.