UI/UX Developer/Designer

Location: UK, Brazil or Toronto (Remote/Hybrid)

Type: Full-Time, Permanent

About LemonEdge

LemonEdge is a next-generation accounting platform built specifically for private capital markets. Our technology powers fund administrators, private equity firms, and asset managers with a flexible, scalable solution that automates complex calculations, enhances transparency, and accelerates operational efficiency.

Since launch in 2020, we have grown to 75+ employees across six continents, backed by leading investors including Blackstone Strategic Innovations and Sidekick Partners. Our fund and portfolio accounting solution supports some of the most complex and largest global clients, with a combined asset base of over $1.4 trillion.

Our culture prioritises speed, ownership, and collaboration. As a scaling business, you will join a fast-paced, entrepreneurial team with the opportunity to make a direct impact on our product, clients, and future growth.

The Opportunity

We are hiring our first dedicated UI/UX Designer to elevate the LemonEdge user experience. Your initial focus will be modernising our WPF application and designing its move to the web—improving themes, icons, navigation, and overall interaction. Over time, you’ll help define our web design language and ensure clear, consistent user journeys across all products.

You’ll work closely with product, development, and implementation teams to gather requirements, create prototypes, and deliver clean, user-friendly designs. This is a high-impact role that will establish the foundation of UI/UX at LemonEdge.

Key Responsibilities

• Hands-on in our .NET/WPF app to modernise UI components, themes, and interactions.
• Lead the redesign of core screens, navigation flows, and shared UI elements within WPF.
• Collaborate with Product and Dev to gather requirements and translate them to UI.
• Create wireframes, flows, and prototypes to validate design direction before coding.
• Implement UI improvements directly in C#, XAML, and related WPF frameworks.
• Optimise performance, accessibility, and responsiveness across the existing desktop app.
• Present design iterations, gather feedback, and iterate quickly.
• Begin laying foundations for web-based UI design systems for the eventual transition.
• Support consistency of UI/UX across desktop and emerging web components.

About You – Ideal Profile

• Strong experience with C#, .NET, and WPF, including hands-on UI development.
• 5–10 years in UI/UX design within complex applications, ideally enterprise SaaS/FinTech.
• Practical experience creating modern desktop UI, with an eye for clean, scalable design.
• Exposure to web frameworks (React, Blazor) and interest in transitioning desktop to web.
• Proficient in design tools such as Figma, Adobe XD, Illustrator, or Photoshop.
• Excellent communicator who collaborates well with developers, product, stakeholders.
• Delivery-focused and able to balance design intent with technical realities.

What Success Looks Like (KPIs & Metrics)

• Delivery of a modernised WPF UI across high-impact areas within the first 6 months.
• Noticeable improvements in look, feel, responsiveness, and usability across the desktop.
• Strong developer–designer collaboration embedded into our SDLC.
• Early design system foundations established to support future web migration.

What We Offer

• A unique opportunity to shape and modernise a core .NET/WPF product used globally.
• The ability to influence long-term design direction as we expand into web technologies.
• A collaborative remote/hybrid culture with autonomy and room to innovate.
• Competitive compensation, equity, and benefits.