Creditas Internet Banking

Context

Creditas runs an internet banking application used daily by retail customers. Banking software has little tolerance for mistakes: every release has to be reliable, every screen has to work for people using a keyboard or a screen reader, and a slow-feeling transfer screen erodes trust fast.

I joined the frontend team to deliver new features and fix defects in a codebase that had grown past 100,000 lines of React and TypeScript.

The problem

Bugs were not spread evenly. A large share came from parts of the app nobody really owned — older modules with inconsistent component structure, duplicated helpers and naming that differed from file to file. Every fix there was risky, because it was hard to know what else a change would touch.

What I did

Refactoring the under-owned parts

Instead of only patching symptoms, I used defect work as a map of where the codebase hurt most and improved those areas proactively:

• Standardised component structure so similar screens are built the same way.
• Extracted reusable utilities to replace copy-pasted logic that drifted over time.
• Unified naming conventions, which made code review and onboarding noticeably easier.

Each change shipped in small, reviewable steps alongside regular feature work, so there was never a risky big-bang rewrite.

Making the app feel faster

Some banking flows depend on several backend calls. I redesigned selected screens and introduced loading skeletons that match the final layout, so content appears progressively instead of the page jumping around. The data didn’t arrive faster — but the interface felt faster and calmer.

Accessibility

I brought key flows in line with WCAG 2.1: ARIA labelling, full keyboard navigation, focus management in dialogs and multi-step flows, and colour-contrast fixes.

Outcome

• 56% fewer defects in the refactored areas.
• More predictable releases and smoother production deployments.
• A more consistent foundation that made the team more confident shipping changes.