Legacy System Migration

For businesses where outdated systems are limiting growth, creating risk, or holding back AI adoption

What You Get

What's Included in Our Legacy System Migration

Key deliverable

Legacy System Assessment

A thorough assessment of the current system — its technical state, business risk, data quality, and the options available for modernisation.

  • Technical audit of current system architecture and codebase
  • Business risk assessment — what happens if this system fails
  • Data audit — volume, quality, and migration complexity
  • Modernisation options analysis — rewrite, replace, or re-platform
Key deliverable

Migration Strategy & Roadmap

A detailed migration plan that sequences the work to minimise business disruption — with clear milestones, rollback plans, and success criteria.

  • Phased migration roadmap with business continuity plan
  • Parallel running strategy for critical operational periods
  • Data migration plan with validation checkpoints
  • Rollback plan for each migration phase
Key deliverable

Modern Replacement Development

The modern replacement system — built to your operational requirements, designed for the workflows your team actually uses, and architected for long-term maintainability.

  • Modern technology stack chosen for longevity and maintainability
  • Feature parity with current system plus targeted improvements
  • Performance and scalability built in from the start
  • Security and compliance requirements addressed by design
Key deliverable

Data Migration & Validation

Complete migration of your historical data to the new system — with full validation to ensure nothing is lost, corrupted, or misaligned.

  • Data extraction and transformation from legacy system
  • Data cleaning and normalisation during migration
  • Automated validation of migrated data against source
  • Historical data accessibility in the new system
Our Process

From Discovery to Delivery

A proven approach to strategic planning

Assessment & Options Analysis
01

01 • Weeks 1–3

Assessment & Options Analysis

Deliverable: Legacy system assessment report with recommended migration approach

View Details
Migration Strategy & Design
02
Build & Migrate
03
Cutover & Decommission
04

Why Trust StepInsight for Legacy System Migration

Experience

  • Delivered complex legacy migrations across multiple industries
  • Experience with custom-built systems, vendor platforms, and hybrid environments
  • Data migrations ranging from thousands to millions of records
  • Zero-downtime migration techniques for business-critical systems
  • 15+ years of combined legacy system modernisation experience across the team

Expertise

  • Legacy codebase assessment and documentation
  • Phased migration strategy and execution
  • Data extraction, transformation, and validation
  • Modern replacement development across web, mobile, and cloud
  • Business continuity planning for critical system transitions

Authority

  • Offices in Sydney, Brussels, and Austin
  • Specialists in mid-market legacy modernisation
  • AI-ready architecture for all modern replacements
  • Fixed-scope assessments before any migration commitment
  • Long-term support partnership after migration completion

Ready to start your project?

Let's talk custom software and build something remarkable together.

Frequently Asked Questions About Legacy System Migration

Through phased migration with parallel running. We keep the legacy system operational throughout the migration, moving functionality and data in phases, and only decommissioning the legacy system once the new one is fully validated and adopted.

All historical data is migrated to the new system with full validation. We build automated validation tools that compare migrated data against the source to ensure nothing is lost or corrupted.

Typically 4–6 months from assessment to completed cutover, depending on system complexity and data volume. We always start with a 2–3 week assessment that produces a precise estimate before any migration work begins.

Every migration phase has a documented rollback plan. We never cut over without the ability to roll back. And we run parallel systems during critical transition periods so the business is never dependent on an untested system.

It depends on what's driving the migration. If the problem is vendor lock-in or cost, re-platforming to a better vendor may be faster and cheaper. If the problem is fundamental capability gaps or maintainability, a custom rebuild gives you the right foundation. We assess both options and give you an honest recommendation.

What our customers think

Our clients trust us because we treat their products like our own. We focus on their business goals, building solutions that truly meet their needs — not just delivering features.

Lachlan Vidler
We were impressed with their deep thinking and ability to take ideas from people with non-software backgrounds and convert them into deliverable software products.
Jun 2025
Lucas Cox
Lucas Cox
I'm most impressed with StepInsight's passion, commitment, and flexibility.
Sept 2024
Dan Novick
Dan Novick
StepInsight work details and personal approach stood out.
Feb 2024
Audrey Bailly
Trust them; they know what they're doing and want the best outcome for their clients.
Jan 2023

Ready to start your project?

Let's talk custom software and build something remarkable together.