Are you available for hire?

Yes. I'm open to on-site, hybrid, or remote roles — backend, cloud, or AI-integrated systems. Direct email is fastest: eddyjunc@gmail.com.

Melbourne, Australia (AEST · UTC+10/+11). I work with teams across AU, APAC, and US time zones.

What do you specialise in?

AWS-native, Python-first backends with a strong AI-integration track record: serverless (Lambda, API Gateway, DynamoDB, OpenSearch), distributed state machines, JWT/Cognito auth, and production RAG / vector-search systems.

What's your AWS experience?

3+ years building production AWS workloads. AWS Certified Solutions Architect — Associate. Hands-on with 125+ Lambda functions, DynamoDB, OpenSearch, S3, API Gateway (REST + WebSocket), Step Functions, Cognito, EventBridge, and Terraform.

About

The short version of who I am, what I do, and why.

→ /experience

$cat ./about/jun-cao.md

>loaded · 1.2kb · ok

Hi, I'm Jun.

I'm a Backend Software Engineer with 3+ years building secure, scalable, cloud-native systems on AWS. I'm currently at Visa Robot in Melbourne, where I lead backend development for a one-stop immigration visa platform — form automation, e-lodgement, CRM, payments, cloud storage, and an AI-powered legal assistant.

I think in distributed systems: API Gateway → 125+ Lambdas → DynamoDB / S3 / OpenSearch / Stripe, glued by Terraform and CI/CD. I'm the engineer who reads the runbook before the page goes off, designs the state machine before writing the function, and pushes hard on the cost graph after the feature ships.

Lately a lot of my work sits at the intersection of backend and AI — I designed and built our production legal knowledge vector DB and the relevance-tuned retrieval that sits behind it.

Outside work I tinker with side projects (a price-watcher daemon, small AWS deploys, and the occasional UI like this one) and study cloud certifications.

// what I bring

Cloud-native by default

I architect for AWS — Lambda, DynamoDB, S3, API Gateway, OpenSearch — with Terraform and CI/CD baked in. I've shipped 125+ Lambda functions that run a real business.

Auth & data safety first

JWT with refresh-token rotation, AWS Cognito, RBAC, audit logging, principle of least privilege — and a healthy paranoia about secrets in pipelines.

AI-integrated backends

Built the production legal AI vector DB at Visa Robot. Comfortable across embeddings, vector search, hybrid retrieval, and prompt orchestration.

Distributed by design

Single-table DynamoDB, async pipelines, idempotent state machines. I default to designs that survive timeouts, retries, and the 3am page.

Pragmatic engineer

Reduced backend infra cost by 35% at Visa Robot. I optimise for the code that ships, the bug that gets fixed, and the team that has to maintain it next year.

// frequently asked

Are you available for hire?: Yes. I'm open to on-site, hybrid, or remote roles — backend, cloud, or AI-integrated systems. Direct email is fastest: eddyjunc@gmail.com.
Where are you based?: Melbourne, Australia (AEST · UTC+10/+11). I work with teams across AU, APAC, and US time zones.
What do you specialise in?: AWS-native, Python-first backends with a strong AI-integration track record: serverless (Lambda, API Gateway, DynamoDB, OpenSearch), distributed state machines, JWT/Cognito auth, and production RAG / vector-search systems.
What's your AWS experience?: 3+ years building production AWS workloads. AWS Certified Solutions Architect — Associate. Hands-on with 125+ Lambda functions, DynamoDB, OpenSearch, S3, API Gateway (REST + WebSocket), Step Functions, Cognito, EventBridge, and Terraform.

More on the experience page, or get in touch via contact.