Estela Valle

Software Engineer

Sainsburys

London

09.2021 - Current

Created and developed backend microservices using Java (Spring Boot), primarily focused on calculating and serving promotions to Argos, Tu, Nectar, Habitat, and Sainsbury’s customers.
Developed and implemented backend payment services, including transaction processing, validation, and integration with third-party payment providers to ensure secure and reliable payment journeys.
Built RESTful APIs consumed by frontend teams and other internal partners; involved in API design and performance tuning.
Worked across multiple teams in agile environments to deliver end-to-end solutions, working with designers, product owners and users.
Contributed to CI/CD pipelines using GitHub Actions, ensuring reliable and automated deployments.
Maintained robust test coverage using JUnit, Jest, and Cypress.
Improved operational monitoring with New Relic, logging, and alerting; participated in incident response on-call rotations.
Used Terraform for infrastructure as code and Docker for containerisation.
Mentored team members, helping them gain confidence to work independently on the codebase.
Actively fostered better collaboration and communication within and between teams.
Balanced full-time work with ongoing part-time university studies.
Developed and tested React/TypeScript UI components in Magnolia CMS, delivered features like automated JPEG background adjustment and integrated third-party review system Bazaarvoice.
Focused on continuously improving technical skills and capabilities through hands-on work and learning.