We are hiring a Backend Software Engineer to build and maintain scalable backend services supporting high-volume product experiences. This is a hands-on contract role for an engineer who can work with general independence, make day-to-day technical decisions, and collaborate with product, design, platform, and engineering teams to deliver reliable backend functionality.
Enterprise experience strongly preferred.
**Key Responsibilities**
- Design, build, and maintain backend services using Java and/or Kotlin, Spring Boot, and Spring Batch or equivalent JVM batch frameworks.
- Develop and evolve REST and GraphQL APIs serving internal services and consumer-facing products.
- Build and tune batch processing pipelines for data-intensive workflows, including ingestion, enrichment, and scheduled jobs.
- Analyze tradeoffs across performance, maintainability, reliability, and delivery speed.
- Participate in code reviews, on-call rotations, incident response, observability, and continuous service improvement.
- Partner with product managers, architects, and fellow engineers to scope work, refine requirements, and deliver against team objectives.
**Qualifications**:
- Must-Have Skills**
- 3+ years of professional backend engineering experience.
- Backend development experience with Java as the primary language or Kotlin.
- Experience working in Java and comfort working in Kotlin environments or codebases.
- Production experience with Spring Boot.
- Production experience with Spring Batch or equivalent JVM batch frameworks.




- Strong fundamentals in REST API design and implementation.
- Hands-on experience building or consuming GraphQL APIs.
- Practical experience using LLM-based coding assistants in day-to-day engineering workflows.
- Ability to speak credibly about when to trust AI-generated code, when to validate it, and when to push back or revise it.
- Solid understanding of relational and/or NoSQL data stores.
- Experience with async messaging such as Kafka or similar technologies.
- Solid understanding of distributed systems concepts.
- Ability to operate with general independence on moderately complex engineering problems and deliver quality work without close supervision.
**Nice-to-Have Skills**
- Experience operating services at large scale, including millions+ of requests per day.
- Exposure to GraphQL federation, Apollo Federation, or similar approaches.
- Observability tooling experience with Datadog, OpenTelemetry, Prometheus, or similar tools.
- Familiarity with CI/CD pipelines.
- Familiarity with Docker, Kubernetes, and cloud platforms.
**Additional Information**:
- Required Tools & Platforms**
- Java
- Kotlin
- Spring Boot
- Spring Batch or equivalent JVM batch frameworks
- REST APIs
- GraphQL APIs
- LLM-based coding assistants such as Claude Code, GitHub Copilot, Cursor, or similar tools
- Relational and/or NoSQL data stores
- Kafka or similar async messaging technologies
**Location, Time & Engagement**
- Remote contract role.
- 40 hours per week.
- Engagement expected to run through March 31, 2027.

📌 120309 - Backend Software Engineer, Java/kotlin (Ciudad de México)
🏢 Lifted, an Upwork Company™
📍 Ciudad de México