AdvOS.
Replacing a 20-year-old legacy system with a modern, secure practice-management platform for a leading Croatian law firm.
Visit advosapp.comFor over two decades, a leading Croatian law firm ran its entire practice - clients, cases, time tracking and billing - on a single-machine Windows application from the early 2000s. Reliable, but frozen in time: no web or mobile access, no modern security model, and increasingly hard to reconcile with new regulation like e-invoicing and Fiskalizacija 2.0.
We designed and built AdvOS - a secure, multi-tenant, web-based platform that maps one-to-one onto how a Croatian law office actually operates. Every hour logged now moves through approvals and exits as a compliant, fiscalized invoice, with zero manual work in between.
Twenty years of workflow, frozen in a desktop app.
The firm's workflows were shaped around a single-machine desktop system down to the keystroke, and any replacement that forced staff to relearn their own practice would fail on arrival. The brief was therefore unusual and precise: modernize the workflows, don't reimagine them - build something contemporary and secure that still maps one-to-one onto how a Croatian law office operates.
Continuous discovery, prototyped before a line of backend.
We ran the project as a continuous discovery loop rather than a big-bang spec: every module started from the firm's real processes, captured in a living specification of over sixty screen definitions. Design was Figma-first, but we also built a fully clickable HTML prototype of the core modules that partners could walk through before any backend was committed - surfacing dozens of domain rules generic legal software gets wrong, each turned into a first-class feature.