API Developer | Hybrid | Contract

ESOL IT SERVICES INC.; Metro Manila; On-site; PHP 500,000 - 900,000; Full time

Job summary

ESOL IT SERVICES INC. is seeking an experienced API Developer to design, develop, integrate, and maintain reliable APIs for business apps and digital platforms. You will collaborate with frontend, QA, product teams and other stakeholders to deliver scalable backend services.

The role emphasizes REST API development, API architecture, and security with strong emphasis on collaboration and continuous improvement of backend systems.

Qualifications

• Bachelor's degree or related field preferred.
• 3–7+ years of API/backend development experience.
• Strong REST API development experience.
• Proficiency in one or more backend languages such as Java, C#, Python, Node.js, or PHP.
• Solid understanding of API architecture, HTTP, JSON/XML, auth and security.
• Experience with relational/NoSQL databases.
• Familiarity with Git and version control workflows.
• Experience with banking/fintech/enterprise apps is highly preferred.
• Understanding of SDLC and coding best practices.

Responsibilities

• Design, develop, and maintain secure, scalable APIs and backend services.
• Build and integrate RESTful APIs based on business requirements.
• Develop backend logic and integrations to support apps and systems.
• Collaborate with frontend and QA teams for seamless API integration.
• Translate requirements into effective API solutions.
• Implement authentication, authorization, validation and error handling.
• Perform API testing, debugging, and performance optimization.
• Investigate integration issues and production defects.
• Create and maintain API docs and integration guidelines.
• Work with databases and external systems for data exchange.
• Participate in code reviews and uphold coding standards.
• Collaborate with QA and DevOps throughout development and deployment.
• Contribute to backend architecture improvements.

Skills

REST APIs

Backend development

Java

C#

Python

Node.js

PHP

API architecture

HTTP protocols

JSON/XML

Authentication/Authorization

Relational databases

NoSQL databases

Git

OpenAPI/Swagger

Education

Bachelor's degree in Computer Science/Info Tech/Software Engineering

Tools

Git

Postman

Swagger/OpenAPI

Job description

About the Role

We are looking for an experienced API Developer to design, develop, integrate, and maintain reliable and scalable APIs that support business applications and digital platforms. The ideal candidate should have strong backend development experience, a solid understanding of API architecture, and the ability to collaborate effectively with frontend developers, QA engineers, product teams, and other technical stakeholders.

Key Responsibilities

• Design, develop, and maintain secure, scalable, and high-performing APIs and backend services.
• Build and integrate RESTful APIs and other API-based services based on business and technical requirements.
• Develop backend logic, services, and integrations to support applications and enterprise systems.
• Collaborate with frontend developers and other engineering teams to ensure seamless API integration.
• Analyze business and technical requirements and translate them into effective API solutions.
• Implement authentication, authorization, validation, error handling, and other API security measures.
• Perform API testing, debugging, troubleshooting, and performance optimization.
• Investigate and resolve integration issues, production defects, and API-related incidents.
• Create and maintain API documentation, technical specifications, and integration guidelines.
• Work with databases and external systems to support reliable data exchange and processing.
• Participate in code reviews and follow established coding, security, and development standards.
• Collaborate with QA and DevOps teams throughout development, testing, deployment, and maintenance.
• Contribute to the continuous improvement of backend architecture, development practices, and API performance.

Qualifications

• Bachelor’s degree in Computer Science, Information Technology, Software Engineering, or a related field is preferred.
• 3–7+ years of experience in API, backend, or software development, depending on level and scope of experience.
• Strong experience developing and integrating REST APIs.
• Proficiency in at least one backend programming language such as Java, C#, Python, Node.js, PHP, or similar.
• Strong understanding of API architecture, HTTP protocols, JSON/XML, authentication, and authorization.
• Experience working with relational and/or NoSQL databases.
• Familiarity with Git and version control workflows.
• Strong troubleshooting, debugging, and problem-solving skills.
• Ability to work effectively with cross-functional technical and business teams.
• Experience working on banking, fintech, financial services, or other enterprise applications is highly preferred.
• Strong understanding of software development lifecycle and coding best practices.

Preferred Qualifications

• Experience with API gateways, microservices, or distributed systems.
• Familiarity with OAuth 2.0, JWT, OpenAPI/Swagger, or similar API standards.
• Experience with cloud platforms such as AWS, Azure, or Google Cloud.
• Exposure to CI/CD pipelines and DevOps practices.
• Experience with API testing tools such as Postman, SoapUI, or similar platforms.
• Knowledge of application security and secure API development practices.
• Experience working in an Agile/Scrum development environment.