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Karolina Szczur

Summary #

Calibre is a bootstrapped, profitable SaaS business offering web performance monitoring, which I co-founded with Ben Schwarz↗. As a founder and Principal Designer, I led design strategy, end-to-end product releases, and created processes that helped us scale the business.

Creating UI systems #

With no designer on staff during the first few years, both marketing and the product were built without the tools to guarantee a cohesive design language. I created two Design Systems (product and marketing) with associated usage documentation to enable our small team to release with confidence. Outside of Figma, I also contributed to live components implemented in Storybook.

Screenshot of the Calibre marketing home page focusing on the top-level heading stating 'Everything you need to improve web performance' with several product images below. The in-focus image shows a Core Web Vitals dashboard with three bar charts for LCP, CLS, and INP. Each chart has different values and colors (red, green and yellow), depending on metric readings.
↑ Above • Preview of selected components from Calibre’s Product Design System, including buttons, alerts, pills, charts, dropdowns, expandable tables, and more.

Thanks to both robust UI Kits, we were able to rapidly release new features and refresh existing pages for consistency in the visual language. Because all Calibre employees are design-savvy, it also empowered them to make positive changes without following a more lengthy, end-to-end design process.

Directing design #

I was responsible for creating a visual strategy for all design aspects of Calibre, including both product and marketing. Easy to use, resilient design can often influence buying decisions, so I always treated it as business critical. Even more so than performance, developer-oriented tools are frequently lacking in this area.

Cohesive and modern UI #

Calibre was initially built by a founder with strong design and product sensibilities. When I joined, I committed to auditing the existing UI and enhancing it with the help of newly established design systems and interface guidelines. Because inclusion is one of my core values, I spent time on information architecture, appearance, and interactions to make sure the UI was easy to understand and navigate, no matter someone’s capabilities.

↓ Below • Snippet from the colour library showing purple shades with accompanying accessible text color pairings, ranked by colour contrast ratio accordingly to WCAG 2.2 guidelines.
Screenshot of five tiles from Calibre's colour system. Each tile has a rectangle filled with colour, colour name (e.g. 'purple-50'), HEX value and several other library colours that can be safely used over that colour to maintain accessibility.
↓ Below • Selected variations of unified, top-level navigation that depends on browsing context and user role.
Screenshot of eight variants of Calibre's top-level navigation. All of them have a Calibre logo on the left-hand side, a search box in the middle and several links on the right-hand side, depending on user's role.
↓ Below • Result of audit and unification work on Calibre’s dropdowns, including different variants and states.
Screenshot of several types of dropdowns in Calibre with all states they might be in (hover, selected, loading and no results in most cases).

Clear marketing showcasing the product #

Marketing design is an art. In the latest iteration of Calibre’s marketing site, I prioritised clear copywriting with high-quality product imagery. While it’s tempting to turn marketing pages into feature listicles, instead, I focused on telling a story of how to successfully use the end-to-end platform. This approach has markedly increased our trial conversions.

Screenshot of the Calibre marketing home page focusing on the top-level heading stating 'Everything you need to improve web performance' with several product images below. The in-focus image shows a Core Web Vitals dashboard with three bar charts for LCP, CLS, and INP. Each chart has different values and colors (red, green and yellow), depending on metric readings.
↑ Above • Preview of the top section of the most recent Calibre marketing home page, showing focus on simplicity and presenting the product with readable, real imagery.

Establishing processes #

I love writing and how it empowers even non-remote teams, so it’s not a surprise I’ve spent a significant chunk of my time creating repeatable processes, templates, and guidelines. Creating processes isn’t only reserved for bigger organisations.

Without locking ourselves into rigid rules, I authored documentation for design principles, approaching customer support (which yielded a consistent 97-100% satisfaction rating), how we use communication channels, an entire hiring strategy, and more. Now, all the Calibre know-how is easily accessible, either for teammates or future you.

Screenshot of several pages in from Calibre's Notion internal knowledge base. The titles of the documents include 'Voice & Tone Guide', 'How we use Figma', 'Brand Color Guidelines', 'Communication Channels', 'Design principles: Forms', and 'How we hire'.
↑ Above • Preview of several knowledge base articles and processes I’ve authored, such as Voice & Tone, a guide to using Figma, interface principles, brand colour guidelines, and hiring processes.

Releasing product features #

The foundations work described above empowered us to release several features that simplified understanding and improving performance for teams small and large. Here are a few selected projects.

Providing real user data without tracking #

With all eyes on Core Web Vitals (a set of core performance metrics for UX, also used as a signal for Google Search algorithm) we unlocked a way of tracking them across synthetic and real user datasets. Often, a roadblock to real user monitoring is the extra cost and need for external scripts. With Core Web Vitals Dashboard, teams can quickly do a health check with neither of those obstacles.

This is an excellent update! Love the instant switch between p75 and the overall histogram. Thanks for your recent focus on bringing RUM into the dashboards, it’s been very helpful.

Simplifying making sense of performance #

Web performance is famously complex, data-rich and known for gatekeeping anyone but developers. One of our guiding principles is making performance accessible and understandable to anyone who expresses interest in the field. Again, the more collaborative and informed your team is, the more success you’re going to have.

This is great, Karolina! I love seeing the LCP time in the render timeline.

Snapshot reports guide readers to quickly spot the most critical performance issues. While they are data-heavy, they use an intentional visual language and content strategy to prioritise the most impactful tasks to focus on.

The main conference room, facing the stage and big display with a CSSConf logo. In front of the display, there's the majority of attendees, speakers and organisers smiling and waving towarsds the camera. There are probably 200 people there.

Fostering collaboration #

Most impactful work happens when cross-functional teams focus on the same goals. This rings even more true for web performance, where stakeholder buy-in can be difficult to get. While project, people, and level of access organisation might sound mundane, it allowed Calibre’s customers to effectively divide areas of responsibility. It made performance a shared initiative, reduced the cognitive load of too much data, and collaborated with external contractors or agencies.

Screenshot of Airline Benchmark team, listing five top airlines accordingly to Skytrax, sorted accordingly to the fastest Interaction to Next Paint. EVA Air is first and Singapore Airlines is last.
↑ Above • Starting page for Airline Benchmarks team, which allows to quickly grasp the state of performance of multiple websites between synthetic and real-user monitoring.
Feature release post
Collaborate on Speed with Teams

Helping prevent UX regressions #

One of the biggest challenges of web performance is not only achieving good metrics, but keeping them that way. Budgets not only allow teams to track key metrics against their goals, over time, but take a proactive approach with at risk notifications. Effective speed work is all about trends, so the earlier teams can take action, the lesser the negative impact on their UX and customers.

Screenshot of Calibre's Budgets dashboard. It shows filtering options set to 'All' budget statuses and 'Mobile' devices'. It shows four colour-coded tiles for four different performance metrics, with labels such as 'Exceeded', 'At risk' and 'Met' depending on the values of the metric. It also lists Pages and Test Profiles affected.
↑ Above • Calibre’s performance budgets dashboard showing budgets in all states for mobile devices. This dashboard is a birds-eye view into how a website is doing against set speed goals.
Feature release post
Set and Meet Speed Budgets