Systems we build

Custom ERP & business systems

The system your business actually runs on — custom ERP and operational software that replaces the tangle of spreadsheets and half-fitting SaaS. Built on a proven open-source core or the right modern stack, tailored to how you work, and owned outright — no per-seat fees, no lock-in.

30 min with a full-stack devAll services

Proof, not promises

Custom ERP & business systems we've shipped

Metal Zbiorniki — Rebuilding a steel-tank maker's sales pipeline — site, configurator, CRM and AI-drafted quotes
Manufacturing · Web + Sales systems + AI
Metal Zbiorniki

Rebuilt a steel-tank manufacturer's sales pipeline end to end — multilingual site, instant-quote configurator, CRM, AI-drafted quotes.

Groomershop — One order cockpit for a high-volume store
Commerce · Order management
Groomershop

One order cockpit for a pet-supplies store doing tens of thousands of orders a month — mirrored live from a desktop ERP with no API.

Covo — An eSIM wallet for international travelers
Fintech · Travel / eSIM
Covo

The backend and mobile apps behind a travel eSIM wallet — an append-only multi-currency ledger, family pooling, instant top-ups.

MyEvaluations — Medical-training SaaS modernized without a rewrite
SaaS · Healthcare / EdTech
MyEvaluations

Modernized a 20-year-old C# monolith powering most US health universities — incrementally, no big-bang rewrite.

How we think, not just what we type

Concepts & patterns we work in

The ideas behind the tools — the patterns we've applied in production, not buzzwords.

The 80/20 modelOwn your stack — no per-seat fees, no lock-inSystems consolidationReplace spreadsheets with validated workflowsIntegrate, don't rip-and-replaceGradual, module-by-module migrationModular monolithEvent-driven modules

Languages, frameworks, infra

What we actually use

The tools and languages we have real, shipped experience in — not a wish list.

Core
Open MercatoPayload CMS
Data layer
MikroORMpgvector
Modules
Order managementCRMInvoicingInventory
Integrations
Polish ERPs (Subiekt · Streamsoft)PaymentsThird-party APIsWebhooks
Search & AI
RAG / LLMs

Explore further

Manufacturing & production systems →Order management & ERP integration →Custom CRM & sales operations →Why Open Mercato →

Bring the napkin sketch.

Thirty minutes with a full-stack engineer, plus a short written report that's yours to keep.

30 min with a full-stack devSee services →

30 minGoogle Calendarno sales deck

Prefer to write? Send us a message →