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Connect and modernize systems

Legacy Modernization. The legacy system is replaced step by step, without a big-bang switchover.

Step-by-step modernization with a planned cutover, jointly agreed operating targets (SLOs) and GDPR-compliant data migration

Proposal within 48 h How we work on it
  1. Workshop
  2. Setup
  3. Sprint
  4. Build & Support

Fixed price after scoping · proposal within 48 h

Reviewed: September 2026

Legacy Modernization
Legacy Modernization
Legacy Modernization

Legacy modernization is the step-by-step replacement of outdated software: the old and new systems run in parallel until data and users have fully moved over.

Outdated systems slow innovation and cause high maintenance costs. We modernize legacy applications to enterprise standards: Strangler Fig pattern with CDC (Change Data Capture) for consistent data migration, Blue-Green/Canary deployments for low-risk cutover, and full observability (Prometheus, Grafana, Alerting). Every migration ships with defined SLOs, documented rollback plans, and runbooks. Security-by-design with IAM/RBAC, Secrets Management (Vault), audit logs, and zero-trust networking. Infrastructure optionally on Kubernetes or Serverless (AWS Lambda/Vercel) with HA/DR concept.

Who it's for

Ideal for established companies with mission-critical legacy systems that need a controlled, low-risk migration with measurable SLOs. Particularly valuable for CTOs and IT leaders who must meet compliance requirements (GDPR, SOC2, ISO 27001) alongside technical modernization.

Key Features

  • Phased migration
  • Cutover with rollback plan
  • Data integrity verified
  • Modern technology stack
  • Observability Integrated
  • Security & Compliance Compliant
  • Debezium
  • Kubernetes
  • API Gateway
  • Microservices
  • Next.js 16
  • Prometheus
  • Grafana

We select the optimal tech stack for your specific requirements

How we work on it

  1. Workshop
  2. Setup
  3. Sprint
  4. Build & Support
(01)

Sprint

Four weeks on one goal, with something that runs at the end.

4 weeks · fixed price after scoping
(02)

Build & Support

We build the project out and stay alongside you once it is live.

after scoping, ongoing · fixed price after scoping; support billed monthly

Included

(01)

Inventory of code, dependencies and interfaces

(02)

Modernisation plan with sequence and risks per module

(03)

Migration of a first, clearly scoped module

(04)

Automated tests that lock in existing behaviour

(05)

Documentation and plan for the remaining modules

Not included

(01)

A complete rebuild in one step (big bang)

(02)

Migrating the entire system within the sprint (continues after scoping in Build & Support)

(03)

Licence and hosting costs of the target platform

How it runs

(01)

Inventory

We analyse code, data and interfaces and identify the riskiest areas.

W1
(02)

Target picture & plan

Target architecture and migration sequence; we pick a first module with low risk and clear benefit.

W2
(03)

First module & handover

Migration of the module alongside the legacy system, tests, cut-over and plan for the remaining modules.

W3-4
(01)

CRM System

Related Use Cases
(02)

Project Management

Related Use Cases
(03)

Invoicing

Related Use Cases
(04)

Crafts & Construction

Relevant Industries
(05)

Healthcare & Care

Relevant Industries
(06)

Gastronomy & Hospitality

Relevant Industries
(01)

Custom software development

Topic page
(02)

AI integration into your tools

Topic page
(01)How do you keep downtime during cutover to a minimum?
We use Blue-Green or Canary deployments where the new system runs parallel to the legacy system. Traffic is gradually shifted (e.g., 5% → 25% → 50% → 100%) while monitoring metrics in real-time. If a metric crosses the threshold we agreed on beforehand, we automatically switch back to the legacy system.
(02)What happens to my data during migration?
We use CDC (Change Data Capture) with tools like Debezium to synchronize data changes in real-time. Dual-write mechanisms and checksum validations ensure data consistency. Before cutover, we perform restore tests and document rollback procedures.
(03)How do you meet compliance requirements (GDPR, SOC2)?
Security is integrated into every phase: IAM/RBAC for access control, HashiCorp Vault for secrets management, complete audit logs, and zero-trust networking. PII data is handled according to data residency requirements. We document all compliance-relevant measures for audits.
(04)How do you measure migration success?
Before migration, we jointly define SLOs for availability, P95 latency and error rate, derived from measurements of the legacy system. We implement monitoring dashboards with error budgets, automated alerting, and incident runbooks. Post-migration reviews compare actual performance against defined targets.
(05)What's your rollback plan if something goes wrong?
Every migration has a documented rollback plan with clear triggers (e.g., error rate > 1%, latency > SLO). With Blue-Green, we switch traffic back at the load balancer – this takes effect in seconds, without waiting for DNS caches. We conduct rollback drills before go-live and train your team on the runbooks.
(06)What infrastructure options do you offer?
Depending on requirements: Kubernetes (EKS/GKE) for complex workloads with autoscaling and service mesh, or Serverless (Vercel/AWS Lambda) for event-driven architectures. Both options with HA/DR concept, defined RTO/RPO, and regular disaster recovery tests.
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Book a call Proposal within 48 h

Fixed price after scoping · proposal within 48 h