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Applix

Backend Developer – Java, Reactive Spring & AWS

Applix

India
Full-Time
Posted 3 days ago

Job Description & Responsibilities

About the Job

We are seeking an experienced Senior Backend Developer to design, develop, and enhance the backend services powering our Dynamic Service Options (DSO) platform. The role involves working across two Java-based reactive backend applications:

  • Authoring Backend – Responsible for ingesting machine parts and service data from cloud data warehouses, validating and enriching datasets through a service-option engine, and publishing processed datasets.
  • Delivery Backend – Consumes published datasets, applies dataset-level authorization, and exposes secure APIs supporting the Dynamic Service Options user experience.

Both platforms leverage Java 17, Spring Boot WebFlux, Project Reactor, PostgreSQL (R2DBC), AWS Lambda, Amazon SQS, ECS Fargate, OpenAPI, Flyway, OpenTelemetry, and CloudFormation.

The ideal candidate is passionate about building highly scalable, event-driven backend systems, follows reactive programming principles, and owns features end-to-end—from API design through deployment and production observability.

Key Responsibilities

Backend Development

  • Design, develop, and maintain reactive REST APIs using Spring Boot WebFlux and Project Reactor (Mono/Flux).
  • Build highly scalable, asynchronous backend services without blocking operations.
  • Develop secure and reusable APIs following OpenAPI-first principles.
  • Implement standardized API contracts, response models, and error handling.

Event-Driven & Cloud Development

  • Build and maintain AWS Lambda functions triggered through:
  • Amazon SQS FIFO queues
  • Amazon EventBridge schedules
  • Implement retry mechanisms, dead-letter queues (DLQs), concurrency controls, and idempotent processing.
  • Integrate with AWS services including:
  • Lambda
  • ECS Fargate
  • S3
  • Secrets Manager
  • DynamoDB
  • Aurora PostgreSQL
  • CloudWatch
  • IAM

Database Development

  • Design and optimize PostgreSQL schemas.
  • Develop reactive data access using Spring Data R2DBC.
  • Build complex SQL queries using jOOQ.
  • Utilize PostgreSQL capabilities including:
  • JSONB
  • ltree hierarchies
  • Partitioning
  • GIN/GIST indexing
  • Author and maintain Flyway database migrations.

Integration Development

  • Integrate with enterprise platforms including:
  • Snowflake
  • ServiceNow
  • Internal Product Catalog Services
  • Entitlement & Identity Services
  • Implement secure JWT authentication and long-running asynchronous workflows.

Performance & Reliability

  • Optimize backend performance using:
  • Caffeine Cache
  • Redis
  • Parallel reactive execution
  • Query tuning
  • Ensure high throughput, scalability, and resilience.

Observability & Monitoring

  • Implement distributed tracing using:
  • OpenTelemetry
  • AWS Distro for OpenTelemetry (ADOT)
  • Create custom metrics, structured logs, dashboards, and production monitoring using:
  • CloudWatch
  • AWS X-Ray
  • Grafana

Testing & Quality

  • Develop comprehensive unit and integration tests using:
  • JUnit 5
  • Mockito
  • Reactor StepVerifier
  • Maintain high code quality through SonarQube.
  • Participate in peer code reviews and mentor engineering team members.

CI/CD & DevOps

  • Contribute to CI/CD pipelines using GitHub Actions.
  • Build Docker images and manage deployments through CloudFormation.
  • Package Lambda artifacts and publish container images to Amazon ECR.

Security

  • Implement secure backend services using:
  • OAuth2 Resource Server
  • Role-based authorization
  • Least-privilege IAM policies
  • AWS Secrets Manager
  • Input validation
  • Follow OWASP secure coding best practices.

Required Skills & Qualifications

Programming Languages

  • Java 17+
  • Modern Java features (Records, Streams, Sealed Classes)

Frameworks

  • Spring Boot
  • Spring WebFlux
  • Spring Security
  • Project Reactor
  • Spring Data R2DBC

Database Technologies

  • PostgreSQL
  • Aurora PostgreSQL
  • R2DBC
  • jOOQ
  • Flyway

Cloud & Messaging

  • AWS Lambda
  • Amazon SQS
  • EventBridge
  • ECS Fargate
  • Amazon S3
  • Secrets Manager
  • CloudWatch
  • IAM
  • AWS SDK v2

Infrastructure as Code

  • CloudFormation
  • AWS SAM / CDK / Terraform (preferred)

API Development

  • REST APIs
  • OpenAPI 3
  • Bean Validation
  • API Versioning

DevOps & Tools

  • Gradle
  • Docker
  • Docker Compose
  • Git
  • GitHub Actions
  • SonarQube

Testing

  • JUnit 5
  • Mockito
  • Spring Boot Test
  • Reactor Test

Engineering Competencies

  • Reactive programming
  • Distributed systems
  • Event-driven architecture
  • Microservices
  • Asynchronous processing
  • System design
  • Strong debugging and problem-solving skills
  • Excellent communication and collaboration abilities

Preferred Skills

  • OpenTelemetry
  • Grafana
  • Prometheus
  • Tempo
  • Loki
  • Snowflake
  • Spring Cloud Function
  • AWS Lambda optimization (SnapStart/CRaC)
  • LocalStack
  • JVM performance tuning
  • Enterprise SSO (Azure Entra ID)
  • OAuth2 Introspection
  • RBAC / Entitlement platforms
  • OWASP Top 10
  • Agile/Scrum methodologies

Technologies

CategoryTechnologies

Programming

Java 17+

Frameworks

Spring Boot, Spring WebFlux, Project Reactor, Spring Security

Databases

PostgreSQL, Aurora PostgreSQL, R2DBC, jOOQ

Cloud

AWS Lambda, ECS Fargate, S3, EventBridge, SQS, IAM, CloudWatch

DevOps

Docker, GitHub Actions, CloudFormation, Gradle

Testing

JUnit 5, Mockito, Reactor Test

Monitoring

OpenTelemetry, ADOT, CloudWatch, X-Ray, Grafana

Security

OAuth2, JWT, IAM, AWS Secrets Manager

What You'll Work On

  • High-volume cloud data ingestion pipelines
  • Reactive microservices for Dynamic Service Options
  • Event-driven AWS Lambda workflows
  • Dataset publishing and lifecycle management
  • Secure REST API development
  • Dataset versioning and permissions
  • ServiceNow orchestration
  • Enterprise product catalog integrations
  • Scheduled backend processing jobs
  • Distributed tracing and production observability
  • Performance optimization for large-scale backend services
  • Cloud-native architecture modernization

Why Join Us?

You'll have the opportunity to build highly scalable, cloud-native backend systems using modern Java, reactive programming, and AWS technologies. This role offers exposure to enterprise-scale distributed systems, event-driven architectures, and end-to-end ownership of mission-critical services while collaborating with experienced engineers in an Agile environment.

Required Skills

JavaAWSAzureDockerSQLRedisGitCI/CDTerraformAgile

Job Details

Employment TypeFull-Time
Work ModeOn-Site
Experience00 years
Positions1

Posted by

N/A

Posted on:

26 Aug 2026

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