Senior IoT Software Engineering (Java & CRM Integration)

This is a remote position.

Location: Remote
Engagement Type: Project-based Assignment; B2B Contract (Outside IR35)
Duration: 6 months with auto renew
Timezone: CET ± 2 hours

Key Deliverables

• Design and develop high-performance, fault-tolerant microservices using Java (Spring Boot) to handle telemetry data from millions of connected IoT devices.
  
  
• Lead the integration efforts between our IoT management platform and Salesforce (or similar CRM/OSS platforms).
  
  
• Build RESTful and GraphQL APIs to expose IoT data (usage, status, location) to downstream systems and partner portals.
  
  
• Interface directly with telecom operator networks to manage SIM provisioning, SMS commands, and connectivity status using industry protocols (SMPP, SS7/REST APIs).
  
  
• Implement message queuing solutions (Kafka/RabbitMQ) to handle the high throughput of device data.
  
  
• Ensure low-latency processing for mission-critical IoT alerts and commands.
  
  
• Collaborate with cross-functional teams including product managers, network engineers, and frontend developers to deliver end-to-end solutions.
  
  
• Troubleshoot and resolve integration issues between internal systems and third-party operator platforms.
  
  
• Participate in code reviews, architecture discussions, and sprint planning sessions.
  
  
• Document technical designs, integration flows, and deployment procedures.
  

Requirements

Ideal Profile

• 5+ years of experience with Core Java, including concurrency and JVM performance tuning.
  
  
• Deep expertise in Spring Boot, Spring Data, and Spring Security.
  
  
• Hands-on experience with cloud platforms such as AWS, Azure, or GCP (Azure preferred for telecom environments).
  
  
• Proven experience integrating cloud applications with Salesforce using REST APIs, SOAP, or Salesforce Connect.
  
  
• Strong experience with SQL and NoSQL databases, as well as stream processing tools like Kafka.
  
  
• Familiarity with IoT protocols including MQTT, CoAP, and LwM2M.
  
  
• Experience integrating with telecom operator APIs for SIM lifecycle management (e.g., AT commands, SMPP, or vendor-specific APIs like Ericsson/Huawei).
  
  
• Understanding of telecom OSS/BSS systems such as Order Management, Billing, or Inventory.
  
  
• Experience working in an Agile/Scrum development environment.
  
  
• Strong problem-solving skills, particularly around distributed systems and network latency.
  
  
• Excellent communication and collaboration skills.
  

• Experience with Docker and Kubernetes for container orchestration.
  
  
• Knowledge of 5G network slicing concepts.
  
  
• Experience with CI/CD pipelines and infrastructure as code (Terraform, CloudFormation).
  

Why Partner with Us?

• Clear scope with no ambiguity over deliverables.
  

• Flexible working arrangements.
  

• Opportunity for repeat engagements based on performance.
  

Selection Process 

1. Proposal Submission
   

   • Submit your professional profile/CV by applying on the role.
     

2. Business Alignment Call
   

   • 30-min virtual discussion with Human Capital Consultant to review scope
     

3. Verification
   

   • Opportunity to complete Castille Vetting (background/compliance checks)
     

4. Client Skills Review
   

   • Direct interview with end client to discuss project specifics
     

   • Project-specific technical assessment (if required)
     

Ongoing Business Support

• Access to CX guidance and market insights through our professional network.