
API/SOA Developer (Freelance)
**Location:** Brussels, Belgium (Hybrid: 2-3 days remote per week)
**Contract Type:** Freelance (Prestation de services)
**Levels \& Experience Required:** Junior (1 year exp.) \| Medior (3 years exp.) \| Senior (10 years exp.)
**Language Requirements:** Fluent in English (3/4) **OR** fluent in Dutch/French (3/4)
### About Smile: Why Join Us?
Passionate about tech, digital, and innovation? Join the 1,800 employees at **Smile**, the European leader in open-source integration, spread across 20 agencies in 9 countries. Collaborative spirit and knowledge sharing are at the heart of our DNA. Our experts push the boundaries of open source every day to build a smarter, more efficient, and more responsible digital world. Here, we don't just follow trends, we create them! Join Smile in Brussels and take part in projects that truly matter!
* **Peer-to-Peer Management:** Our proximity management by peers fosters dialogue and the implementation of a tailored career path.
* **Continuous Learning:** Because the digital sector is in constant motion, Smile is committed to making you an expert in your field, thanks to a comprehensive training offer: access to an e-learning platform, financing of certifications, and robust knowledge-sharing tools.
* **Vibrant Community:** Your year will be animated by group and agency events: annual convention, participation in trade fairs, summer party, and plenty of formal \& informal afterworks.
### Role Overview
On behalf of our fast-growing division, we are looking for **API/SOA Developers** at different seniority levels (**Junior, Medior, and Senior**) to join our consultant pool in Brussels.
In this role, you will be key to developing, securing, and maintaining modern API and Service-Oriented Architectures (SOA). Working on behalf of our premier client in Brussels, you will build clean, secure integrations and play a central part in bridging legacy systems with modern cloud infrastructure.
### Key Responsibilities
Depending on your level of seniority, your responsibilities will include:
* **API \& SOA Development:** Developing high-quality backend APIs and services using **Java** within SOA, REST, and event-driven architectures.
* **API Management \& Integration:** Implementing and configuring integration points across enterprise platforms such as **Axway, Apigee, or WSO2**.
* **Security \& Vulnerability Management:** Incorporating robust security standards (OAuth2, JWT, SOAP security) and securing code using tools like **Snyk** and **PKI (Public Key Infrastructure)**.
* **Cloud \& CI/CD Pipelines:** Deploying and managing applications within Public Cloud environments, actively utilizing **Git** and automation-driven **CI/CD** pipelines.
* **Testing \& Quality Assurance:** Conducting thorough automated testing of web services to ensure system stability, resilience, and high performance.
* **Agile Collaboration:** Working within an **Agile/Scrum** framework, using **Jira** and **Confluence** for documentation, tracking, and sprint activities.
### Your Profile
* **Experience:**
* **Junior:** \~1 year of experience in backend/API development.
* **Medior:** \~3 years of solid experience in API \& middleware development.
* **Senior:** 10 years of deep expertise in complex enterprise integration and software development.
* **Core Technical Skills:**
* Proficient in **Java** development applied to APIs.
* Strong knowledge of API/Web Service standards and protocols (**OAuth2, JWT, SOAP**).
* Hands-on experience with API Gateway / ESB platforms such as **Axway, Apigee, or WSO2**.
* Familiarity with **Event-Driven Architecture** and public cloud concepts.
* Solid understanding of security tools and practices (**Snyk, PKI**).
* Experience with **Git** , **CI/CD** workflows, and web services testing frameworks.
* **Methodology:** Comfortable working in **Agile/Scrum** squads with tools like **Jira** and **Confluence**.
* **Languages:** Working proficiency (minimum 3/4) in **English** OR **French/Dutch**.
### The Recruitment Steps
1. **First Contact:** A phone call to discuss your aspirations and what we can offer you.
2. **Meeting:** An opportunity to get to know each other and explore your professional background.
3. **Business Interview:** A discussion with one of our experts to assess your skills and define your goals.