Enterprise integration · Legacy modernisation

System Integration and Legacy Modernisation

Enterprise system integration and legacy modernisation for medium and large companies in Hungary and the EU: connecting ERP, CRM, WMS, MES, banking, HR, and e-commerce systems. API-first strategy, EDI, ESB, microservices, gradual legacy migration with the strangler fig pattern - without disrupting operations. Audit HUF 2-4M (~€5k-€10k), full programme HUF 30-300M (~€77k-€770k).

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Audit HUF 2-4M (~€5k-€10k) Strangler fig - no big bang CTO-as-a-Service available 20+ year legacy integratable

Trusted Partners

Proud to work with leading companies

Services

System integration services

The 6 main service directions that cover 90% of an enterprise IT stack.

System integration audit

Mapping the current IT stack: which systems exist, how they communicate (or fail to), where data redundancy lives, where the bottlenecks are. Output: integration map + roadmap, priorities.

API-first strategy

A unified API layer for every existing and new system - REST, GraphQL, gRPC. Documented, authenticated, rate-limited, monitored in one place. API gateway (Kong, AWS API Gateway, Cloudflare Workers).

EDI and B2B integration

EDIFACT, ANSI X12, OpenPEPPOL, AS2/AS4 - automotive, retail, pharma, logistics supplier/customer integrations. Hungarian EDI standard (NAV) supported as well.

ESB and message queue

Enterprise Service Bus (Kafka, RabbitMQ, ActiveMQ, NATS) - asynchronous communication, event-driven architecture, guaranteed delivery, replayability for audit.

Legacy modernisation

Modernising legacy systems (Oracle Forms, AS/400, Lotus Notes, FoxPro, Delphi, .NET Framework 1.x-3.x, monolithic Java) - strangler fig pattern, gradual migration without disturbing the business.

Cloud & on-prem hybrid

Hybrid integration: critical on-prem systems (SAP, banking core) connected to cloud services (CRM, marketing, BI). Site-to-site VPN, AWS Direct Connect, Azure ExpressRoute, secure one-way/two-way data sync.

6 phases

The 6 phases of system integration

Not a big bang project. From audit onwards, gradually over 12-36 months - measurable business value at every step.

Discovery & audit (4-6 weeks)

Stakeholder interviews, system map, data flow diagrams, risk assessment. Output: integration master plan, budget, ROI forecast.

Strategy & architecture (2-4 weeks)

Target architecture, technology stack choice (REST vs GraphQL vs Kafka), security model, governance. Integration is not a project - it is a programme.

API gateway & ESB foundation (2-4 months)

Building the integration backbone: API gateway, service mesh, message queue, monitoring. The "infrastructure" each individual integration is built on.

Per-integration delivery (3-12 months)

Prioritised integrations delivered in parallel. A typical integration takes 4-12 weeks, depending on how well-documented the source system's API is.

Data sync & migration (2-4 months)

Historical data migration from legacy systems into the new ones. Data cleansing, deduplication, master data management. Validation, audit, rollback procedures.

Stabilisation & handover (1-3 months)

Performance tuning, monitoring fine-tune, runbooks, on-call setup, documentation. Onboarding the in-house team, mentor role for 3-6 months.

How We Work

Our Process

Meticulous planning, seamless execution, and creative problem-solving -- that's how we achieve remarkable results.

Concept

No cookie-cutter solutions here. We map out your business goals, market landscape, and competition, then build a strategy designed to deliver measurable results.

Concept

No cookie-cutter solutions here. We map out your business goals, market landscape, and competition, then build a strategy designed to deliver measurable results.

Concept

No cookie-cutter solutions here. We map out your business goals, market landscape, and competition, then build a strategy designed to deliver measurable results.

Design

Wireframes, prototypes, and UI/UX designs built on real user insights. Every click, every layout is engineered to maximize conversions and engagement.

Design

Wireframes, prototypes, and UI/UX designs built on real user insights. Every click, every layout is engineered to maximize conversions and engagement.

Design

Wireframes, prototypes, and UI/UX designs built on real user insights. Every click, every layout is engineered to maximize conversions and engagement.

Development

Agile development with cutting-edge technologies, weekly demos, and full transparency. You'll always know exactly where your project stands.

Development

Agile development with cutting-edge technologies, weekly demos, and full transparency. You'll always know exactly where your project stands.

Development

Agile development with cutting-edge technologies, weekly demos, and full transparency. You'll always know exactly where your project stands.

Testing

Automated and manual testing across every platform and browser. Nothing goes live until it's been tested to the breaking point and passed with flying colors.

Testing

Automated and manual testing across every platform and browser. Nothing goes live until it's been tested to the breaking point and passed with flying colors.

Testing

Automated and manual testing across every platform and browser. Nothing goes live until it's been tested to the breaking point and passed with flying colors.

Launch & Support

Launch day is just the beginning. Monitoring, performance optimization, and ongoing support ensure your solution gets better every single day.

Launch & Support

Launch day is just the beginning. Monitoring, performance optimization, and ongoing support ensure your solution gets better every single day.

Launch & Support

Launch day is just the beginning. Monitoring, performance optimization, and ongoing support ensure your solution gets better every single day.

Concept

No cookie-cutter solutions here. We map out your business goals, market landscape, and competition, then build a strategy designed to deliver measurable results.

Concept

No cookie-cutter solutions here. We map out your business goals, market landscape, and competition, then build a strategy designed to deliver measurable results.

Concept

No cookie-cutter solutions here. We map out your business goals, market landscape, and competition, then build a strategy designed to deliver measurable results.

Design

Wireframes, prototypes, and UI/UX designs built on real user insights. Every click, every layout is engineered to maximize conversions and engagement.

Design

Wireframes, prototypes, and UI/UX designs built on real user insights. Every click, every layout is engineered to maximize conversions and engagement.

Design

Wireframes, prototypes, and UI/UX designs built on real user insights. Every click, every layout is engineered to maximize conversions and engagement.

Development

Agile development with cutting-edge technologies, weekly demos, and full transparency. You'll always know exactly where your project stands.

Development

Agile development with cutting-edge technologies, weekly demos, and full transparency. You'll always know exactly where your project stands.

Development

Agile development with cutting-edge technologies, weekly demos, and full transparency. You'll always know exactly where your project stands.

Testing

Automated and manual testing across every platform and browser. Nothing goes live until it's been tested to the breaking point and passed with flying colors.

Testing

Automated and manual testing across every platform and browser. Nothing goes live until it's been tested to the breaking point and passed with flying colors.

Testing

Automated and manual testing across every platform and browser. Nothing goes live until it's been tested to the breaking point and passed with flying colors.

Launch & Support

Launch day is just the beginning. Monitoring, performance optimization, and ongoing support ensure your solution gets better every single day.

Launch & Support

Launch day is just the beginning. Monitoring, performance optimization, and ongoing support ensure your solution gets better every single day.

Launch & Support

Launch day is just the beginning. Monitoring, performance optimization, and ongoing support ensure your solution gets better every single day.

Concept

No cookie-cutter solutions here. We map out your business goals, market landscape, and competition, then build a strategy designed to deliver measurable results.

Concept

No cookie-cutter solutions here. We map out your business goals, market landscape, and competition, then build a strategy designed to deliver measurable results.

Concept

No cookie-cutter solutions here. We map out your business goals, market landscape, and competition, then build a strategy designed to deliver measurable results.

Design

Wireframes, prototypes, and UI/UX designs built on real user insights. Every click, every layout is engineered to maximize conversions and engagement.

Design

Wireframes, prototypes, and UI/UX designs built on real user insights. Every click, every layout is engineered to maximize conversions and engagement.

Design

Wireframes, prototypes, and UI/UX designs built on real user insights. Every click, every layout is engineered to maximize conversions and engagement.

Development

Agile development with cutting-edge technologies, weekly demos, and full transparency. You'll always know exactly where your project stands.

Development

Agile development with cutting-edge technologies, weekly demos, and full transparency. You'll always know exactly where your project stands.

Development

Agile development with cutting-edge technologies, weekly demos, and full transparency. You'll always know exactly where your project stands.

Testing

Automated and manual testing across every platform and browser. Nothing goes live until it's been tested to the breaking point and passed with flying colors.

Testing

Automated and manual testing across every platform and browser. Nothing goes live until it's been tested to the breaking point and passed with flying colors.

Testing

Automated and manual testing across every platform and browser. Nothing goes live until it's been tested to the breaking point and passed with flying colors.

Launch & Support

Launch day is just the beginning. Monitoring, performance optimization, and ongoing support ensure your solution gets better every single day.

Launch & Support

Launch day is just the beginning. Monitoring, performance optimization, and ongoing support ensure your solution gets better every single day.

Launch & Support

Launch day is just the beginning. Monitoring, performance optimization, and ongoing support ensure your solution gets better every single day.

What we integrate

The complete enterprise IT stack

8 system categories where we have deep integration experience. A new vendor folds into the process within 1-2 weeks.

ERP systems

SAP S/4HANA, SAP ECC (PI/PO), Microsoft Dynamics 365 Finance & Operations, Oracle JD Edwards, Infor M3, IFS, Epicor, NetSuite, custom ERPs

CRM and sales stack

Salesforce (SOAP/REST API), HubSpot, Microsoft Dynamics 365 Sales, Pipedrive, Zoho CRM, MS Outlook / Exchange, phone systems (3CX, Twilio)

Logistics and manufacturing

WMS (SAP EWM, Manhattan, custom), MES, SCADA, PLCs (OPC UA, Modbus), carriers (DPD, GLS, DHL, Foxpost), TMS

Financial systems

Banking APIs (OTP, Erste, K&H, Raiffeisen - Hungary; PSD2 Open Banking across the EU), invoicing (Számlázz.hu, Billingo, KulcsSoft, Stripe Invoicing, Xero, QuickBooks), accounting (RLB60), NAV Online Számla 3.0, EKAER, Revolut Business

HR and payroll

Nexon, KulcsSoft Payroll, Workday, BambooHR, SAP SuccessFactors, ATS systems (Workable, Greenhouse, Recruitee)

Marketing and e-commerce

Shopify, WooCommerce, Magento, Mailchimp, Brevo, Klaviyo, GA4, Meta Ads, Google Ads, marketing automation platforms

IT and infrastructure

Active Directory, Microsoft 365, Google Workspace, monitoring (Datadog, Grafana), SIEM (Wazuh, Splunk), ticketing (Jira, ServiceNow)

Industry-specific

Healthcare (HL7 FHIR, DICOM), education (Neptun, ETR, Moodle), government (KAÜ, ÜFK in Hungary), banking (SWIFT, ISO 20022, Open Banking PSD2)

FAQ

System integration - Frequently Asked Questions

What is system integration and when do you need it?

System integration = connecting different business systems (ERP, CRM, WMS, MES, e-commerce, banking, HR) so that data appears in one place and processes flow across them. Typical signs: you re-enter the same data in multiple systems manually, reports take weeks, customer data is stored in 5 places in different versions, errors compound. If you see this in your business - you need system integration.

How much does a system integration project cost in 2026?

Audit + strategy (entry point): HUF 2-4M (~€5k-€10k), 4-6 weeks. A single integration (e.g. ERP ↔ webshop): HUF 3-8M (~€7,700-€20,500), 2-4 months. Mid-sized integration programme (5-10 systems, API gateway, ESB): HUF 30-80M (~€77k-€205k), 9-15 months. Enterprise integration (legacy modernisation + 15+ systems + multi-site): HUF 80-300M (~€205k-€770k), 18-36 months. Annual maintenance 15-25%. ROI is usually 12-24 months from manual-work and error reduction.

Can you integrate with 20+ year old legacy systems? (AS/400, Oracle Forms, Lotus Notes)

Yes - and this is typically 30% of every project. AS/400 (IBM iSeries / IBM i): JDBC adapter or IBM HATS, RPG code understanding. Oracle Forms / APEX: PL/SQL adapter, Forms→REST migration. Lotus Notes: Domino REST API or LotusScript adapter. FoxPro / Clipper: ODBC or file-based export. .NET Framework 1.x-3.x: WCF / SOAP wrapper. Old SAP R/3: BAPI / IDoc. Methodology: strangler fig - building a new API layer over the legacy system and replacing it function by function.

What is the difference between ESB (message queue) and REST API integration?

REST API: synchronous request-response. One system calls another and waits for the answer. Simple and quick to build. Problem: if the receiver is down, the data is lost. Does not scale under heavy load. ESB / message queue (Kafka, RabbitMQ): asynchronous, message-based. The data goes into a queue; the receiver reads it when ready. Scales, guaranteed delivery, replayable for audit. More complex architecture. We typically use REST for user-facing flows and ESB for background processes / batch jobs.

What is API-first strategy, and why does it matter?

API-first = every new internal system, every new feature gets an API first, the UI second. The API is the "official" interface - every integration goes through it. Benefits: 1) new systems are immediately integrable, 2) the UI can be built by anyone (web, mobile, AI agent), 3) partners (B2B customers, suppliers) can integrate too, 4) the transition between microservices and monolith is easy. Long-term, an API-first strategy reduces system integration cost by 3-5x.

Do you offer full legacy modernisation - or only partial work?

We work at the full programme level. Our legacy modernisation methodology: 1) audit and target architecture (4-8 weeks). 2) Strangler fig - new microservices take over functions one by one and the old system gradually disappears. 3) Data migration in the same gradual fashion. 4) Big bang switchover NEVER - 12-36 months of phased migration. The methodology guarantees the business keeps running during migration. We also work on individual tasks (e.g. replacing one module), but the strategic-partner position delivers the most value.

Can you integrate with Hungarian banks and NAV?

Yes. NAV Online Számla 3.0 (mandatory in Hungary): outgoing/incoming invoice reporting, procurement-side queries, EKAER. Hungarian banks: OTP Bank Open API (PSD2), K&H Bank, Erste, Raiffeisen, MagNet, MKB / Takarékbank - payment initiation, account balance, transaction history. Hungarian accounting software: Számlázz.hu, Billingo, KulcsSoft, RLB60. EU-wide banking integration: Open Banking (PSD2) via Tink, GoCardless. Hungarian EDI: NAV standard, Hungarian Post logistics EDI.

What does CTO-as-a-Service / Integration Architect mean?

If you do not have an in-house IT leader, or they lack experience with complex system integration, we offer an external CTO / Integration Architect role. 2-8 days a month from a senior expert who: 1) supports you in strategic decisions, 2) negotiates with vendors on your behalf, 3) manages the in-house team on the integration project, 4) reviews code and architecture, 5) presents technical status to the board. Typical engagement is 3-12 months at HUF 800,000-3,500,000/month (~€2,050-€8,975/month). The most efficient form of cooperation for high-LTV clients.

AI capabilities

How AI fits into this solution

What AI can do, how to integrate it, what to comply with - and how to keep your data on-prem.

● What AI can do here

Intelligent data mapping

LLM proposes field mappings between two systems - e.g. SAP MATNR ↔ Salesforce Product_Code__c.
Bad-data detection

Inconsistent, duplicate, or malformed records flagged across source and target systems.
Translation layer

Different business concepts (Customer vs Partner vs Account) auto-translated mid-flow.

● How we integrate it

Custom Python integration layer

FastAPI + LangChain / LangGraph orchestrator: every integration in code, versioned, tested. Not a no-code platform - a production-grade, monitored Python service that lives in your CI/CD.
Schema evolution handling

When a source API changes, the AI agent notices and proposes mapping updates - no broken integration.
Audit + explainability

Every AI decision is logged: why this record went there. For compliance and troubleshooting.

Compliance

GDPR

Personal data is processed only on a documented legal basis. Data minimisation, purpose limitation, and audit trail enforced by design.
EU AI Act

Risk-based classification of every AI use case (minimal / limited / high risk). Mandatory transparency, human oversight, and CE-style conformity for high-risk systems.
NIS2

In essential and important sectors AI must follow security-by-design: access control, logging, incident reporting, supply-chain risk for any model provider.
ISO 27001 / SOC 2

When required: ISO 27001 / SOC 2-aligned controls, including key management, RBAC, audit, vulnerability management.

Local / on-prem deployment

Ollama / llama.cpp

Open-weight models (Llama 3.x, Mistral, Qwen, Gemma) running on your own GPU server or even CPU. Zero data sent to third parties.
vLLM / TGI

Production-grade inference servers for self-hosted endpoints. Concurrent users, streaming, function calling supported.
Sovereign cloud

For organisations without on-prem GPU: deployment on EU / Hungarian sovereign cloud (e.g. dedicated tenant), with data residency contracts.
Hybrid

Sensitive content always local; for non-sensitive batch tasks frontier models (Claude, GPT) via DPA-backed API where allowed.

Data security model

No training on your data

Whether self-hosted or vendor API, we contractually exclude your data from any training set.
PII redaction before prompt

Automatic PII detection and masking before any prompt leaves your perimeter - pseudonymisation as a hard rule.
Per-role access

Every AI surface uses your existing IAM (Entra ID / Keycloak / Okta) - the AI only sees what the user is allowed to see.
Full audit

Every prompt, response, and tool call logged with user, time, and source - replayable on demand.

How it connects

How does system integration relate to other projects?

System integration is rarely a standalone project - it almost always has an ERP, CRM, WMS, or webshop as its anchor.

The most common integration lines: custom ERP ↔ webshop ↔ banking; CRM ↔ marketing automation ↔ email; WMS warehouse system ↔ ERP ↔ EDI partners.

The intelligent parts of the flow are delivered by Python + LangChain process automation: document extraction, agent flows, decision support. For organisations under NIS2, the entire integration surface lives under NIS2 compliance requirements - logged, with a full audit trail.

Solutions

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