Sandra Margol

Frontend-focused software developer with 3+ years' commercial experience at measurable.energy, where I own frontend architecture across customer-facing IoT energy platforms. Specialise in React.js, SvelteKit, TypeScript, and real-time data systems built on AWS, WebSockets, and Socket.IO. Comfortable across the stack with Node.js, Express, and PostgreSQL, and continuing to grow backend and cloud depth.

Software Developer - measurable.energy

(2023-01)

VC-backed Series A IoT energy startup building AI-powered smart sockets that automatically identify and eliminate wasted energy in buildings. Small, dynamic measurable.energy team - broad ownership and end-to-end work across ambiguous problems.

• Own frontend architecture across customer-facing IoT energy platforms, acting as the primary technical authority for frontend decisions, system design, and long-term maintainability.
• Led delivery of customer dashboards with real-time data visualisation for IoT energy monitoring, built in SvelteKit, TypeScript, Tailwind CSS, and DaisyUI.
• Drove testing migration from Cypress to Vitest and Playwright - improved CI/CD debugging visibility, cut paid tooling costs, and simplified pipeline maintenance.
• Extended and improved a real-time notification system using AWS SQS, S3, WebSockets, Socket.IO, and Sequelize ORM, processing event-driven messages to power live frontend updates.
• Designed custom SVG device visualisations and socket components in Figma, then implemented for production use across the platform.
• Collaborated with product and engineering on technical discovery, evaluating technical trade-offs, architecture direction, scalability requirements, and implementation strategy for new features.
• Implemented frontend authentication including token refresh, secure cookies, CORS, protected routes, and session management in SvelteKit.
• Built backend APIs in Node.js, Express, and Sequelize ORM against PostgreSQL, applying appropriate data modelling techniques and efficient querying strategies to support scalable application performance.
• Applied software design patterns, component abstraction, and reusable architecture principles to improve maintainability, testability, and long-term evolution of frontend applications.
• Wrote automated component and end-to-end tests in Vitest and Playwright, and participated in code reviews and production debugging across the stack.

Administrator - Franklin House Care Home

(2014-01 - 2023-01)

• Managed payroll and resident financial administration in a fast-paced environment alongside studying for a self-taught transition into software.

Healthcare Assistant (Bank) - Hillingdon Hospital NHS Trust

(2014-09 - 2018-09)

• Worked across high-pressure NHS environments requiring teamwork, adaptability, and clear communication.

Course - The Complete ReactJS Course - Udemy (2022 - 2022)

Course - Computer Science 101: Data Structures, Algorithms & Software Engineering Fundamentals - Udemy (2022 - 2022)

Bootcamp - Complete Web Development Bootcamp - Udemy (2021 - 2022)

NVQ Level 3 - Business Administration - Lifetime (2018 - 2022)

Level 2 - English and Mathematics - T2 Business Solutions (2012 - 2013)