Walmart Global Tech

Written by Tasos Piotopoulos

Lead Engineer | MBA Candidate | M.Sc. Software Engineering & Ubicomp

I joined in 2017 via Jet.com (Walmart’s recent e-commerce acquisition at the time), as a Senior Software Engineer in the Dublin office. Within a year I was asked to lead two squads in the Supply Chain organization, and over the following four and a half years I was promoted twice: to Senior Software Engineer / Squad Lead in Feb 2018, then to Staff Software Engineer in Jan 2019. The team continued to operate under the Jet.com brand during my early years there, before fully consolidating into Walmart Global Tech.

Across that time, my work was personally responsible for over $20m in direct cost savings, the reduction of production incidents and pages to a historical minimum, and the creation of three new full-blown teams.

Selected systems delivered

Associate Delivery
Delivery estimation and customer promise
Shipment tracking
Yard management (optimization of inbound and outbound shipments in fulfillment centers)
Ship from Store: US, Mexico, Canada
Seamless returns
Shipment management with direct carrier integration and extended fulfillment capabilities
Competitive Intelligence data platform

Responsibilities as a Staff Engineer

Designed cloud-native systems, gathered feedback, iterated, and drove them to completion in a lean / agile / DevOps-friendly fashion
Facilitated stakeholder, cross-team, and cross-function synchronization: building trust, planning work, setting expectations, providing estimates, reporting progress, eliminating waste, and improving outcomes. This often meant traveling across Walmart’s sites in the US and beyond.
Worked with engineers of all levels to grow both their soft and hard skills
Identified high-value opportunities and influenced the supply-chain technology road map

Technologies and practices

Cloud-native development · Site Reliability Engineering · DevOps · Microservices · Event Sourcing · Data Engineering · Domain-Driven Design · CI/CD · Distributed Systems · Azure · GCP · Kafka · Kafka Connect · Docker · Kubernetes · Consul · Nomad · Scala · Java · F# · C# · CosmosDB · Cassandra · SQL Server · Spark · Hadoop · Hive · Presto · BigQuery · REST · GraphQL · Protobuf · Prometheus · Grafana · Splunk · Dynatrace · Azure DevOps · Jenkins · Slack bots · Git · Swagger · API Design · Jira