Based in Sydney, ready to relocate, visa sponsorship required. Reach me at ashyferny@gmail.com.
Fifteen years building the systems underneath products that millions of people use every day. The globally distributed load balancer behind Apple device activations. The real-time backend powering Canva Live. The internal platform that 8,000 Walmart engineers shipped ecommerce on.
I work at the layer where correctness, latency, and cost collide, and I stay hands on. Lately that means LLM fine-tuning, retrieval augmented generation, and agentic workflows alongside the distributed systems work I have always done.
Apple · Principal Engineer, Device Activations
- Owned a globally distributed load balancer sustaining 99.999% availability for device activation traffic
- Led a team of 12 engineers across the activations platform
Canva · Live Collaboration and Search
- Led development of five real-time collaboration products: Canva Live, Talking Presentations, Reactions, Remote Control, and Playlist
- Grew those surfaces to 10M+ monthly active users in two years, on a platform serving over a billion presentations a year
- Scaled Canva Search from 20M to 80M MAU, a 4x increase in served traffic
Walmart · Platform Engineering
- Built core platform systems for configuration management, auto-generated CRUD APIs, and parallel deployment orchestration
- Those systems served an 8,000-developer ecosystem building and scaling ecommerce
- Core contributor to the migration off a proprietary platform onto an open-source stack, part of a program Walmart credited with $100M+ in annual savings
Atlassian · Search Infrastructure
- Architected an active-active load balancer on ZooKeeper fronting Elasticsearch clusters
- Cut search downtime by 20+ hours per quarter and lifted search NPS by 15 points
eBay · Platform
- Built and open-sourced Regressr, a regression testing framework for HTTP services, now maintained under the eBay GitHub organization
| Project | What it is |
|---|---|
| bigpipe ⭐ 25 | Facebook's BigPipe pagelet architecture, implemented for the Java web platform. Parallel pagelet fetching on JSP/Servlet containers. |
| Regressr | Command line regression testing for HTTP services. Built at eBay, open sourced under the eBay org. |
| dagalti | Dynamic caching proxy that cuts local developer startup time. |
| spark-top-products-dashboard | End to end streaming architecture: Kafka into Spark into Redis into Streamlit. |
| tiny-llama-fine-tuning | Instruction fine-tuning a Llama model to run on Apple Silicon. |
| downloadcleanupagent | A local agentic workflow that triages and cleans a Downloads folder. |
| napkin-math | Rust toolkit for back-of-envelope system performance estimation. |
Five granted and published US patents in real-time collaboration and distributed platform systems.
- Systems and methods for interactive presentations · US 20230205552
- Storing and replaying presentations with video and audio · US 20230205808
- Remotely controlling electronic presentations · US 20230076902
- Increasing throughput of a PaaS system · US 9342369 B2
- Verification of complex multi-application and multi-node deployments · US 20140109082
- Lessons Learnt from Building Reactive Microservices for Canva Live · Canva Engineering
- Building a Data-Driven Autocorrection System · Canva Engineering
- Introducing Regressr, an Open Source Tool to Regression Test HTTP Services · eBay Tech Blog
- 22 Recommendations for Building Effective High Traffic Web Software · High Scalability
- An Implementation of Consistent Hashing in Java · Personal blog
- Take-Home Coding Tests: Signal or Noise? · Personal blog
- Why Australia Struggles to Build a Thriving Tech Ecosystem · Personal blog
AI/ML LLM fine-tuning, RAG, LangGraph, agentic workflows, Prefect
Languages Java, Go, Python, Kotlin, Scala, TypeScript
Distributed Kafka, Spark, Redis, ZooKeeper, consistent hashing, active-active topologies
Cloud AWS (EC2, RDS, DynamoDB, SNS/SQS), GCP (BigQuery, Dataform, Pub/Sub)
Frameworks Spring, gRPC, GraphQL, Temporal, Protobuf
Search Elasticsearch, Apache Solr at index and serve scale
Infrastructure Kubernetes, Helm, Terraform, Spinnaker, ArgoCD
Also running Tentacle Software, a boutique engineering consultancy, between full-time roles.