Enterprise Java Engineer (Argentina, Remote)

We’re looking for a Java engineer who is genuinely good at modernizing legacy enterprise applications — the kind of work where you inherit a decade-old codebase running on Java 8 and an application server nobody wants to talk about, and you get it onto a modern JDK and Spring Boot without breaking the business.

This is not greenfield work. You’ll be reading a lot of unfamiliar code, building test coverage where none exists, untangling dependency graphs, and making incremental changes that ship safely. The engineers who do this well are the ones who are patient with old code, rigorous about verification, and able to explain tradeoffs to a client who is nervous about touching a system that has been running fine for eight years.

You’ll work alongside network architects, cloud architects, software developers, and security engineers on high-impact client projects. We provide many opportunities for growth and will cover the cost of relevant education and certification.

• Migrate enterprise Java applications from legacy JDKs (7/8/11) to modern LTS releases (17/21)
• Move applications off traditional application servers (WebSphere, WebLogic, JBoss/EAP, Tomcat) onto Spring Boot
• Handle the unglamorous parts: javax → jakarta namespace migrations, Ant/Ivy → Maven/Gradle build conversions, dependency and CVE remediation
• Build characterization and regression tests around code that has none, so migrations can be verified rather than hoped about
• Refactor incrementally using patterns like strangler fig — keeping systems shippable throughout, not big-bang rewrites
• Containerize and prepare modernized applications for cloud deployment
• Work directly with client engineering teams: explain the plan, justify the sequencing, and leave them able to maintain what you built

• • 3+ years of professional Java experience, including meaningful time in enterprise/JEE environments
  • Demonstrated experience modernizing or migrating existing Java applications — not just building new services
  • Strong command of modern Java (records, sealed types, pattern matching, virtual threads) and fluency reading older idioms (raw types, EJBs, XML-heavy configuration)
  • Deep Spring Framework and Spring Boot experience, including migrating applications onto it
  • Hands-on with legacy Jakarta EE / J2EE stacks: EJB, JAX-RS/JAX-WS, JMS, JSP/JSF, JNDI
  • Solid with Maven and/or Gradle, including multi-module builds and dependency conflict resolution
  • Testing discipline: JUnit 5, Mockito, Testcontainers, and comfort writing tests for code that was not designed to be testable
  • Relational database and ORM experience: JPA/Hibernate, schema migration tooling (Flyway, Liquibase), and enough SQL to debug what Hibernate actually emitted
  • Containerization with Docker, and familiarity deploying to a major cloud (AWS, GCP, or Azure)
  • Comfort with Git, CI/CD pipelines, and cloud-based dev workflows
  • Excellent written and verbal communication — you will be client-facing
  • Self-motivated, able to work independently and drive work to completion
  • Must be based in Argentina and available to work primarily on Eastern Time

Great to Have

• Experience with automated refactoring tooling: OpenRewrite, Error Prone, Eclipse Transformer, or the JDK migration analyzers (jdeps, jdeprscan)
• Monolith decomposition experience, or a strong point of view on when not to decompose
• AWS, GCP, or Azure certifications
• Experience with AWS services (ECS/EKS, Lambda, RDS, S3)
• Kubernetes in production
• Observability tooling: OpenTelemetry, Micrometer, distributed tracing across a migration boundary
• Infrastructure-as-code (Terraform, CDK, Pulumi)
• Frontend exposure — React/TypeScript or legacy Angular/JSP — enough to modernize a UI layer when a project calls for it
• Prior consulting or client-facing engineering experience

Sela is a global cloud partner, dedicated to guiding our clients in their cloud journey. With our deep relationships with top cloud platforms (AWS, GCP, Azure) and our expertise in building resilient cloud infrastructure, we enable our clients to ‘Cloud Better.’ Our team has over three decades of experience delivering excellence and thought leadership to clients. We take pride in our strong engineering culture, our drive for excellence, and our supportive team.