Full Stack Developer

ABOUT THE ROLE

As a Full Stack Developer at 321, you will be a technical leader responsible for building and maintaining sophisticated web applications, integrations, and digital experiences that power our client's marketing technology infrastructure. You'll work across the entire technology stack—from database architecture and API integrations to front-end interfaces and user experience design—while leveraging modern AI-assisted development tools to accelerate delivery and innovation.

This role sits at the intersection of technical execution, creative problem-solving, and strategic technology implementation. You'll bring expertise in both back-end systems integration and front-end development, with a strong eye for UI/UX design principles and a forward-thinking approach to AI-powered development workflows.

WHAT YOU'LL DO

Back-End Development & Systems Integration

• Build and maintain robust API integrations connecting CRM platforms (HubSpot, Salesforce, High Level), marketing automation tools, and third-party services.
• Design and implement database architectures that support complex marketing workflows, customer journey tracking, and campaign performance analytics.
• Develop server-side logic, authentication systems, and data processing pipelines to support client marketing initiatives.
• Create and maintain RESTful APIs and webhooks that enable seamless data flow between platforms and applications.

Front-End Development & UI/UX

• Design and develop responsive, high-performance web applications and client-facing interfaces with exceptional user experiences.
• Translate strategic requirements and creative briefs into functional, intuitive digital products.
• Implement modern front-end frameworks and best practices to ensure accessibility, performance, and cross-browser compatibility.
• Collaborate with creative team members to bring design concepts to life while maintaining technical feasibility and scalability.
• Conduct user testing and iterate on interfaces based on feedback and analytics.

AI-Assisted Development & Innovation

• Leverage AI development tools like Replit, GitHub Copilot, and other AI-assisted coding platforms to accelerate development cycles and improve code quality.
• Explore and implement emerging AI technologies to enhance client solutions, including automation, personalization, and intelligent decision-making.
• Build prototypes and proof-of-concepts rapidly using AI-powered development environments.
• Stay current on AI development tools and techniques, sharing knowledge with the broader team.

Technical Leadership & Collaboration

• Partner with Client Success, Digital, and Creative teams to scope technical requirements and translate business objectives into technical solutions.
• Provide technical guidance on feasibility, timelines, and architecture decisions for client projects.
• Document code, systems, and processes to ensure knowledge transfer and maintainability.
• Troubleshoot complex technical issues across the full stack and provide solutions that balance immediate needs with long-term stability.
• Support technical aspects of client onboarding, particularly for CRM implementations and marketing automation projects.

WHAT YOU HAVE

• 5+ years of experience in full stack development, preferably supporting marketing technology or agency environments.
• Strong proficiency in back-end languages and frameworks (Node.js, Python, PHP, or similar) with experience building APIs and integrations.
• Expertise in front-end technologies including HTML, CSS, JavaScript, and modern frameworks (React, Vue, or Angular).
• Demonstrated experience with CRM and marketing automation platforms (HubSpot, Salesforce, High Level, or similar) including custom integrations and implementations.
• Solid understanding of UI/UX principles with ability to design intuitive, user-centered interfaces.
• Experience with database design and management (SQL and NoSQL databases).
• Proficiency with AI-assisted development tools such as Replit, GitHub Copilot, Cursor, or similar platforms.
• Experience with version control (Git), CI/CD pipelines, and modern development workflows.
• Understanding of web security best practices, HIPAA compliance considerations, and data protection standards.
• Strong problem-solving skills with ability to debug complex issues across multiple systems.
• Excellent communication skills with ability to explain technical concepts to non-technical stakeholders.
• Self-directed and proactive, with ability to manage multiple projects and priorities simultaneously.
• Bonus: Experience with healthcare, legal, or other regulated industry technical requirements.