Senior Backend Developer

Compunnel, Inc.; Toronto; On-site; CAD 80,000 - 100,000; Full time

Job summary

Compunnel, Inc. is seeking a Software Developer IV based in Toronto, Ontario. The successful candidate will focus on enhancing REST APIs for backend services and will integrate with internal and external APIs using JSON/XML.

Qualified applicants should have over 8 years of backend development experience, especially in Java and REST APIs. Strong skills in data mapping and developing error handling mechanisms are essential. Experience in financial services and with cloud environments like Azure or AWS is a plus.

Qualifications

• 8+ years’ experience in backend development (Java / REST APIs).
• Experience integrating with external/internal APIs (JSON/XML payloads).
• Strong skills in data mapping and transformation.

Responsibilities

• Build and enhance REST APIs for backend services.
• Integrate with internal and external APIs (JSON/XML).
• Implement data mapping and transformation logic.
• Develop error handling, retry, and fallback mechanisms.
• Modify and extend existing legacy and batch integrations.

Skills

Backend development

REST APIs

Data mapping

Error handling

JSON/XML integration

Job description

JOB SUMMARY

This role is for a Software Developer IV with a focus on CAD and back-end development. The successful candidate will be responsible for building and enhancing REST APIs for backend services, integrating with internal and external APIs using JSON/XML, and implementing complex data mapping and transformation logic. This role also involves developing robust error handling, retry, and fallback mechanisms to ensure system resilience. Additionally, the developer will be modifying and extending existing legacy and batch integrations, and actively supporting testing, bug fixing, and deployment cycles.

Key Responsibilities

• Build and enhance REST APIs for backend services
• Integrate with internal and external APIs (JSON/XML)
• Implement data mapping and transformation logic
• Develop error handling, retry, and fallback mechanisms
• Modify and extend existing legacy and batch integrations
• Support testing, bug fixing, and deployment cycles

Required Qualifications

• 8+ years’ experience in backend development (Java / REST APIs)
• Experience integrating with external/internal APIs (JSON/XML payloads)
• Strong skills in data mapping and transformation
• Experience implementing error handling and fallback logic
• Ability to work with existing systems and modify legacy or batch integrations

Preferred Qualifications

• Experience working on financial services or pricing-related systems
• Familiarity with batch processing frameworks (PL/SQL, schedulers, ETL)
• Understanding of API security basics (OAuth, tokens, headers)
• Exposure to cloud environments (Azure, AWS)
• Experience of working with high-volume transaction systems