Prometheas Technologies
OutSystems practiceOutSystems · Modernization

De-risk legacy replacement with rapid low-code delivery.

Legacy system modernization fails because it takes too long and costs too much to get to parity. We use OutSystems to rebuild legacy workflows (ERP, CRM, custom databases) incrementally, delivering business value in weeks instead of years.

What it is

Legacy Monolith Modernization

Legacy Modernization on OutSystems focuses on wrapping or replacing monolithic systems (Java, .NET, mainframe applications, legacy custom portals) with a modern web/mobile interface and agile service layer. By integrating with existing databases and legacy APIs, we build transactional frontends that modern workforces expect, while maintaining core record-keeping systems behind the scenes.

When we recommend it

Fit signals.

  • Your legacy business app requires expensive desktop licensing or VPNs
  • Making a single database field change takes months of change requests
  • Your legacy system is running on out-of-support platforms or custom codebases
  • You need custom workflow features that your legacy ERP does not support
Capabilities

What we deliver in Legacy Modernization.

Every capability below is practiced across multiple production engagements — not a scoping checklist.

Incremental replacement

  • Co-existence architecture & database replication
  • Legacy database schema mapping (SQL Server, Oracle)
  • Monolith decomposition (page-by-page migration)

Agile integrations

  • Legacy SOAP, REST, and EDI integrations
  • Custom OutSystems integration studio extensions (.NET/C#)
  • Active Directory & Single Sign-On (SAML/OAuth) mapping
Engagement patterns

The shapes this work
usually takes.

Legacy wrapper sprint

A 6-week engagement to build a mobile or modern web frontend over a legacy database, exposing blocked fields to mobile users.

Full system replacement

Incremental replatforming of a complex legacy CRM/ERP application, delivering functional modules in 3-week phases.

What goes wrong

Pitfalls we've seen
and how we avoid them.

Recreating the legacy system pixel-for-pixel

The biggest pitfall is replicating outdated legacy workflows in OutSystems. We focus on business outcomes, not recreating legacy UI patterns.

Ignoring architecture patterns

OutSystems makes it easy to build quickly, which can lead to circular dependencies. We enforce clean-architecture (4-Layer Canvas) guidelines.

FAQ

Common questions about Legacy Modernization.

We connect using secure VPNs, AWS Direct Connect, or OutSystems private clouds, exposing legacy SQL or Oracle databases through standard connectors.

Other OutSystems modules

Legacy Modernization on your roadmap?

Thirty minutes with Vikram. Architecture sketch, candid second opinion, scope estimate — no slides.

Book the call