Services / Legacy Modernization

Behaviour-preserving legacy application modernization that doesn't break the business.

For PowerBuilder, Oracle Forms, legacy Java and .NET applications. Parity-tested, slice by slice, with the legacy system running until the new service earns the traffic.

How the method works Covered legacy stacks

Parity Verification Harness100% PARITY

Legacy Output (PowerBuilder)MatchModern Service (.NET Core API)

Calc_Tax(ID=8419): $1,482.40PASSCalc_Tax(ID=8419): $1,482.40

Rule_Eligibility(Flags=0x4A): TRUEPASSRule_Eligibility(Flags=0x4A): TRUE

Post_Ledger_Batch(100 recs): OKPASSPost_Ledger_Batch(100 recs): OK

Shadow execution in production. Every business transaction is run through both legacy and modern code in parallel until 100% behavior parity is verified over 30 days.

PowerBuilderOracle Forms / PL-SQLLegacy Java / StrutsASP.NET / VB6COBOL & Mainframe

What enterprise leaders face

The dilemma of mission-critical legacy applications.

"The original developers retired 5 years ago. The business runs on rules embedded in PL/SQL triggers that nobody fully documents."

VP Engineering, Financial Services

"Big-bang rewrites failed twice before. We cannot risk a 2-year rewrite project that stalls at 80% completion."

CIO, Logistics Provider

"Automated code converters produce unmaintainable spaghetti code. We need modern, clean architecture."

Head of Architecture, Enterprise Tech

Risk Register

Four fatal risks of legacy modernization and how we neutralize them.

RISK 01

Undocumented Business Logic

Decades of edge-case bug fixes live inside stored procedures rather than specs.

Our Mitigation: Automated runtime trace capture records real production executions to build exact behavioral test harnesses before writing line one of modern code.

RISK 02

Big-Bang Cutover Failure

Switching off the legacy monolith all at once creates catastrophic business disruption when unpredicted edge cases occur.

Our Mitigation: Strangler-fig pattern with parallel shadow execution. Slices are migrated incrementally and routed based on traffic percentage.

RISK 03

Unmaintainable Machine Output

Transpiled code produced by automated translation tools is unreadable by modern developers.

Our Mitigation: Human-in-the-loop AI-assisted refactoring. We extract clean domain models and write idiomatic TypeScript / C# / Java with comprehensive test suites.

RISK 04

Scope & Budget Overruns

Unbounded discovery phases drag on for months without delivering usable software.

Our Mitigation: Slice-based fixed-fee milestones. Each 4-week iteration delivers a production-ready microservice that handles real business traffic.

The Modernization Method

Our 4-stage behavior-preserving migration pipeline.

STAGE 01

Discovery & Test Harness Construction

We trace legacy application execution, isolate domain boundaries, and generate automated regression test suites directly from production database inputs/outputs.

AST (Abstract Syntax Tree) parsing of legacy code bases
Database dependency graph mapping
Golden test dataset generation

STAGE 02

Incremental Slice Extraction

We extract high-value business domains slice by slice into clean, modern microservices or cloud-native serverless functions.

Clean Architecture & Domain-Driven Design (DDD)
Automated OpenAPI / Swagger spec generation
Full CI/CD pipeline set up with 90%+ unit test coverage

STAGE 03

Shadow Parallel Execution

Both legacy and modern systems process live production traffic simultaneously. Automated assertions flag any subtle logic drift immediately.

Zero-impact shadow proxy router
Real-time byte-for-byte response comparison
Automatic rollback upon anomaly detection

STAGE 04

Traffic Migration & Decommissioning

Gradual traffic shifting (1% → 10% → 100%) until the modern service earns full production control and legacy components can be safely retired.

Canary deployment & blue-green routing
Legacy database sync & CDC (Change Data Capture)
Complete handover documentation & team enablement

Supported Stacks

Legacy technologies we specialize in modernizing.

PowerBuilder

DataWindows, PFC framework, NVOs migrated to React / Angular frontends and .NET Core / Node.js services.

Oracle Forms & PL/SQL

Forms triggers, PL/SQL packages, Oracle Reports converted to clean Java / Spring Boot microservices with modern Web UIs.

Legacy Java / Struts

EJB 2.x, JSP, Struts monoliths refactored to Spring Boot 3, REST APIs, and containerized Docker / Kubernetes deployments.

.NET Framework & VB6

VB6, ASP.NET WebForms, WCF services migrated to modern .NET 8, C#, and cloud-native microservices.

Frequently Asked Questions

Common questions about our modernization service.

How do you guarantee 100% business logic parity?

We capture production data streams and run automated regression test suites across both the legacy and modern codebases in parallel. The modern service is only promoted to live traffic once zero discrepancies exist across millions of real transactions.

Do we need complete documentation of our legacy app before starting?

No. Most legacy systems we encounter have outdated or missing documentation. Our static code analysis tools and AST parsers extract the business rules and dependency graphs directly from your source code and database schemas.

How long does a typical modernization engagement take?

Instead of multi-year monolith rewrites, our incremental strangler-fig approach deploys the first modernized production slice within 8–12 weeks, with subsequent domain slices delivered every 4 weeks.

Who owns the intellectual property and code generated?

You retain 100% ownership of all source code, test suites, architecture diagrams, and deployment pipelines created during the project.

Get Started

Modernize your legacy application safely.

Schedule a technical architecture assessment to analyze your legacy codebase and estimate your modernization timeline.

Book a Technical Assessment