Full-Stack Web Developer - AI-Driven Marketing Tools

• Permanent, Full-Time Position.
• In-person at London or Manchester 2-days per week. Remote 3 days per week.
• Senior-Level Position
• £60,000 Annual Salary

Kaizen is a performance marketing agency that delivers innovative Search & Social strategies for the world's leading brands including LEGO and Adidas.

We’re looking for a highly capable and independent Web Developer to design and build new AI-augmented SEO and digital marketing tools from scratch.

These tools will gather marketing data from external APIs, process it asynchronously in the backend, enrich it using AI models, and deliver results via simple, performant web interfaces that our team can utilise on a daily basis.

This is a greenfield opportunity where you'll be responsible for both backend and frontend development, so strong full-stack experience is essential.

Job Responsibilities

• Own full project delivery from prototype to production-ready MVP.
• Architect and develop custom backend systems using Python and libraries and frameworks of your choice. 
• Build scalable asynchronous task queues
• Create simple frontend interfaces for internal usage
• Integrate and manage third-party APIs such as ChatGPT, AHREFS & Google APIs
• Build and maintain the company website, powered by WordPress APIs
• 3+ years commercial experience in utilising Javascript libraries and frameworks for web development.
• Managing server hosting to deploying apps on websites utilising GitHub or command-line interfaces.

Technical Requirements

• Python 3.9+
• Relational databases (preferably PostgreSQL or SQLite)
• Strong ability to build React frontend apps
• RESTful API development & third-party integrations
• Experience using LLMs or AI APIs (e.g., Google Gemini, OpenAI)
• Experience working with WordPress APIs (headless WordPress/REST)
• Git for version control
• You will be asked to demonstrate examples of existing tools you have built