Data Migration

Legacy System Migration Services

Modernize Without Losing Your History

Transform decades of legacy data into modern, accessible formats. We specialize in extracting data from mainframes, AS/400, COBOL systems, and proprietary platforms while preserving every record and business rule.

75+
Legacy Migrations
50+
Years of Data
100%
Data Preserved
85%
Quality Improvement

What is Legacy System Migration?

Bringing decades of data into the modern era

Legacy system migration involves extracting data from outdated technology platforms-mainframes, AS/400, COBOL applications, flat files, and proprietary databases-and transforming it for modern systems. This often includes decades of historical data that represents invaluable business knowledge.

Unlike standard database migrations, legacy migrations require reverse-engineering data formats, understanding undocumented business rules embedded in code, and often reconstructing lost metadata. The data may be stored in formats no longer commonly understood or supported.

Our legacy migration approach preserves not just the data, but the context and meaning behind it. We document business rules, validate historical accuracy, and ensure your organization retains full access to its institutional knowledge in a modern, maintainable format.

Key Metrics

100%
Data Preservation
All historical records migrated
85%
Quality Improvement
Data issues resolved during migration
100%
Business Rules
Critical logic documented and preserved
70%
Cost Reduction
Legacy maintenance eliminated

Why Choose DevSimplex for Legacy Migration?

Deep expertise in legacy technologies

Legacy system migrations require specialized knowledge that's increasingly rare. Our team includes engineers with hands-on experience in mainframe environments, COBOL programming, and legacy database systems-expertise that's essential for successful migrations.

We understand that legacy systems often contain business logic that was never formally documented. Through careful analysis and collaboration with your subject matter experts, we identify and preserve these critical rules during migration.

Data quality is typically a major concern in legacy migrations. We implement data profiling, cleansing, and enrichment as part of the migration process, so you emerge with not just migrated data, but better data than you started with.

Requirements

What you need to get started

Legacy System Access

required

Access to legacy system for data extraction, including necessary credentials and documentation.

Subject Matter Experts

required

Team members who understand legacy business processes and data meanings.

Target Platform

required

Modern platform selected and provisioned for receiving migrated data.

Historical Documentation

recommended

Any available system documentation, data dictionaries, or specifications.

Data Retention Policies

optional

Guidelines on what historical data must be preserved.

Common Challenges We Solve

Problems we help you avoid

Undocumented Business Rules

Impact: Critical business logic embedded in code may be lost during migration.
Our Solution: Code analysis, SME interviews, and comprehensive documentation of discovered rules.

Data Quality Issues

Impact: Decades of data entry without validation leads to inconsistencies.
Our Solution: Data profiling, cleansing rules, and quality improvement during migration.

Proprietary Formats

Impact: Data in formats that modern tools cannot directly read.
Our Solution: Custom extraction routines and format conversion expertise.

Your Dedicated Team

Who you'll be working with

Legacy Systems Analyst

Analyzes legacy code and data structures to understand business logic.

15+ years including mainframe/AS400

Data Migration Engineer

Develops extraction and transformation pipelines.

ETL expertise, multiple platforms

Data Quality Specialist

Profiles data, develops cleansing rules, validates outputs.

Data governance certified

How We Work Together

Extended engagement with knowledge transfer to ensure institutional knowledge is preserved.

Technology Stack

Modern tools and frameworks we use

ETL Tools

Custom extraction pipelines

Python

Transformation scripts

SQL

Data manipulation

Custom Scripts

Legacy format handling

APIs

Modern integration

Data Quality Tools

Cleansing and validation

Legacy Migration ROI

Modernizing legacy systems delivers significant cost and capability benefits.

70-90% reduction
Maintenance Costs
Immediate
10x improvement
Data Accessibility
Post-migration
Full modern APIs
Integration Capability
With new platform

Why We're Different

How we compare to alternatives

AspectOur ApproachTypical AlternativeYour Advantage
Legacy ExpertiseMainframe/COBOL/AS400 experienceModern systems onlyCan handle any legacy platform
Business LogicSystematic discovery and preservationData-only focusInstitutional knowledge retained
Data QualityCleansing integrated with migrationMigrate as-isImproved data in new system

Our Process

A proven approach that delivers results consistently.

1

Legacy System Analysis

2-4 weeks

Analyze legacy systems, data structures, and embedded business logic.

System analysis reportData inventoryBusiness rules documentationMigration assessment
2

Data Mapping & Design

3-4 weeks

Map legacy data to modern structures with transformation rules.

Data mapping documentTransformation rulesTarget schema designQuality rules
3

Extraction Development

3-5 weeks

Build custom extraction routines for legacy data sources.

Extraction scriptsTest extractsData profiling reportsQuality baseline
4

Transformation & Cleansing

4-6 weeks

Transform data formats and apply cleansing rules.

Transformation pipelineCleansed dataQuality reportsException handling
5

Migration & Validation

3-4 weeks

Load data to target platform with comprehensive validation.

Migrated dataValidation reportsReconciliationIssue resolution
6

Documentation & Handover

2-3 weeks

Document institutional knowledge and transition to operations.

Full documentationBusiness rules catalogTraining materialsKnowledge transfer

Frequently Asked Questions

What legacy systems can you migrate from?

We have experience migrating from mainframes (IBM, Unisys), AS/400/iSeries, COBOL applications, dBase, FoxPro, Paradox, flat files, and various proprietary systems. If you have data in an older system, we can likely extract and migrate it.

How do you handle undocumented business rules?

We use a combination of code analysis, data pattern analysis, and structured interviews with subject matter experts. We systematically document all discovered rules and validate them before migration.

Can you improve data quality during migration?

Yes, data quality improvement is a standard part of our legacy migrations. We profile the data, identify issues, develop cleansing rules, and validate improvements. Most clients see 85%+ reduction in data quality issues.

How long does a legacy migration take?

Legacy migrations typically take 8-20 weeks depending on system complexity, data volumes, and the amount of business logic that needs to be discovered and preserved. Complex multi-system environments may take longer.

What happens to the legacy system after migration?

After validation and a parallel run period, the legacy system can be decommissioned. We recommend maintaining read-only access for a transition period and archiving the original system for reference if needed.

How do you ensure historical data is preserved?

We validate 100% of records through automated reconciliation, checksum verification, and sampling. Historical data is migrated with full audit trails and timestamp preservation to maintain its integrity and legal validity.

Ready to Get Started?

Let's discuss how we can help transform your business with legacy system migration services.