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Modernización de Sistemas Legados: Do Monolito aos Microservizos

Zespół ESKOM.AI 2026-03-12 Tempo de lectura: 6 min

Technical Debt as a Growth Bottleneck

Legacy systems are the paradox of enterprise IT — they work because they have supported critical business processes for years, yet they simultaneously block innovation, generate growing maintenance costs, and create security risks. Monolithic applications written a decade ago do not integrate with modern services, do not scale elastically, and require increasingly hard-to-find specialists to maintain.

Modernization does not mean throwing everything away and rewriting from scratch. It is a systematic transformation process — from analyzing the existing system, through designing the target architecture, to safely migrating data and gradually deploying new components.

Modernization Strategies

Not every system requires a complete rewrite. We match the strategy to the situation:

  • Re-platform — moving to new infrastructure (e.g., containerization) without changing the code. Fast, low risk.
  • Re-architecture — rewriting to a microservice architecture while preserving business logic. Greater effort, but long-term benefits.
  • Strangler Fig — gradually replacing parts of the monolith with new services until the old system is fully replaced. Minimal risk, longer process.
  • Big Bang — one-time replacement. Risky, but sometimes the only sensible approach for heavily outdated technologies.

The Role of AI in Modernization

Artificial intelligence accelerates every stage of modernization. Code analysis — AI scans legacy code for dependencies, duplication, and potential issues. Code generation — AI agents generate new microservice code based on specifications and existing business logic. Automated testing — a full testing pyramid (unit, integration, E2E, security, performance) is generated and executed automatically.

As a result, an MVP of the new system is built in weeks rather than months, and code quality is verified by thousands of automated tests at every stage.

Safe Data Migration

Migrating from a legacy system is not just about rewriting code — it is about safely transferring years of accumulated business data. We design ETL processes, validate data integrity at every stage, and ensure a period of parallel operation of the old and new systems. Rollback plans at every stage guarantee that in case of problems, you can safely revert to the previous version.

Cloud Migration

Modernization often goes hand in hand with cloud migration — or a hybrid cloud architecture. Not every workload should go to the cloud. We analyze costs, performance requirements, regulatory constraints, and security needs, recommending the optimal model: public cloud, private cloud, hybrid, or on-premise. The key is right-sizing — selecting instances to match actual needs, not peak load, with auto-scaling for demand spikes.

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