Harmonic Case Study - Building a Scalable Safari Extension

Harmonic Security needed a Safari extension to match its Chrome and Firefox versions but faced uncertainty due to Safari’s unique technical constraints and lack of internal expertise. Through iterative development, early feasibility prototyping, and a successful ChatGPT integration, Understanding Solutions delivered a production-ready Safari extension with full feature parity, leaving Harmonic equipped with documentation, upskilled teams, and a scalable foundation for future enhancements.

The Challenge the Client Faces

Harmonic Security needed a Safari browser extension that mirrored the functionality of its existing Chrome and Firefox extensions. However, due to the significant differences between Safari’s WebKit engine and other browsers, there was uncertainty about whether feature parity could be achieved. The client’s team was unfamiliar with Safari’s technical requirements, and the engagement began with limited clarity on feasibility or deployment. Harmonic needed a delivery partner who could explore unknowns, work iteratively, and build confidence over time.

Understanding Solutions' Approach

Understanding Solutions deployed a consultant to work in two-week sprints, enabling Harmonic to adapt scope and priorities in real-time as technical clarity emerged. The project began with a lightweight prototype demonstrating intercept capability across a select number of priority sites. This proved critical in establishing early feasibility and stakeholder confidence.
A major technical challenge was integrating Safari with OpenAI’s ChatGPT. Understanding Solutions led development of a custom intercept mechanism to capture requests to ChatGPT, extract user-specific data such as user profile and type and build a framework that could eventually support a modal window to flag and display sensitive information. This foundational integration was treated as a primary hurdle, with downstream work dependent on its successful completion.
Once the ChatGPT integration was achieved, Understanding Solutions began extending functionality across the remaining six priority sites. The client’s flexibility with site order allowed the team to optimise for technical simplicity and efficiency, with each site taking an estimated 2–3 days to implement after foundational architecture was in place.
Throughout the engagement, Understanding Solutions adjusted delivery sequencing based on ongoing discovery and evolving priorities. Comprehensive documentation and knowledge transfer were postponed until the core architecture was finalised, reducing the risk of rework and ensuring accuracy. Once the underlying framework was stable, detailed documentation was created covering code structure, technical decisions, and recommendations for future enhancement.

The Outcome

Harmonic Security received a fully functioning Safari extension with feature parity to their existing Chrome and Firefox versions. Understanding Solutions navigated high ambiguity and shifting priorities, ultimately delivering a production-grade solution built to scale.
The client’s initial uncertainty around technical feasibility was replaced by tangible, deployable results, and renewed confidence. The engagement not only resulted in a working extension but also improved the client team’s internal understanding of Safari, WebKit, and Apple development environments.
As a result of Understanding Solution’s flexible, outcomes-first approach, the client extended the engagement to unlock additional value—supporting visibility features, TypeScript transitions, and enhancement strategies based on evolving user needs. With comprehensive documentation in place and meaningful knowledge transfer completed, Harmonic is well-positioned to own and evolve the solution long-term.