Vanilla Javascript Developer

Sigma Software is an international technology partner with over 24 years of experience delivering impactful digital solutions for global businesses.

With a team of 2,000+ professionals, the company collaborates with leading brands such as AstraZeneca, Viaplay, Volvo, and Scania, helping them scale, innovate, and stay competitive in rapidly evolving markets.

Operating across more than 20 countries, with 40+ offices in Europe and the Americas, Sigma Software combines global reach with strong local expertise. The company has delivered projects for over 500 clients, spanning industries such as fintech, healthcare, automotive, and media.

We are looking for a JavaScript developer to join and strengthen the team. This role sits at the intersection of client-facing integration work and technical software development, responsible for connecting marketing platforms to client websites and email infrastructure, combining front-end JavaScript expertise with API knowledge, data pipeline awareness, and strong cross-team collaboration skills.

Key Responsibilities

Client Onboarding & Integration

• Set up website integrations including page type definitions, real-time variables, SPA fixes, event tracking, and cart/catalog tracking
• Configure email service provider (ESP) integrations including email capture, unsubscribe logic, prospect/customer sync, and identity resolution
• Execute ESP migrations and replatforming projects, ensuring safe transitions and comprehensive testing

Ongoing Client Support

• Update ESP configurations, event tracking, and data synchronization settings post-launch
• Implement custom onsite JavaScript for campaigns, overlays, and multi-step interactions
• Build and maintain Airflow DAGs for recurring data imports/exports and eligibility filters
• Add dynamic email content and SKU-level tracking for product recommendations

Advanced Development & Troubleshooting

• Conduct feasibility assessments and scope new client requests
• Develop end-to-end integrations with new email service providers
• Diagnose and resolve live client-facing issues, including root cause analysis and safe deployment of fixes
• Provide technical consultation to cross-functional teams and participate in pre-onboarding alignment meetings

Qualifications

Required Technical Skills

• Vanilla JavaScript (ECMAScript 5+) — Primary language for all integration work
• HTML / CSS — Essential for building and troubleshooting onsite campaigns and visual implementations
• REST APIs — Core competency for integrating with email service providers and third-party platforms
• jQuery — Practical experience with DOM manipulation and event handling

Required Tools & Platforms

• Chrome DevTools
• Looker Dashboards

Domain Knowledge

• Event Tracking Implementation — Understanding on how to implement behavioral tracking events (product views, add-to-cart, SKU selection, category views)
• Email Service Provider (ESP) Integrations — Understanding of email capture, unsubscribe handling, prospect/customer synchronization, and URL ID lookup workflows
• Campaign JavaScript — Ability to write custom JavaScript logic for onsite experiences, including multi-step flows and post-submit behavior

Nice-to-Have Technical Skills

• PHP — Beneficial for ESP integration backend work
• Apache Airflow — Basic familiarity with data pipeline orchestration; comprehensive onboarding and documentation provided
• Postman — Experience testing and documenting API endpoints
• Git / Version Control — Understanding of the code management, collaboration, and deployment workflows

Soft Skills

• Problem-Solving — Strong analytical mindset with ability to diagnose root causes and implement sustainable solutions
• Communication — Clear, proactive communication with both technical and non-technical stakeholders across multiple teams
• Code Quality — Commitment to writing maintainable, safe, and thoroughly reviewable code
• Cross-Functional Collaboration — Comfortable working alongside account managers, implementation specialists, and QA teams to deliver client success
• Attention to Detail — Precision in testing, documentation, and deployment to ensure client-facing reliability
• Ready to learn and develop skills