James Allman / JA Technology Solutions LLC
Legacy system migration that protects what works
Migration is rarely just a technical conversion. Long-lived systems contain years of business rules, reporting logic, integration behavior, and custom workflows. I help organizations move to better platforms while preserving the behavior their operations depend on.
Approach
My approach starts with understanding why the current system works — not just what it does, but what business behavior depends on it. Migration planning then addresses data, logic, integrations, and workflows as a connected whole, not isolated technical tasks.
I emphasize phased change over big-bang replacement. Each phase is validated and reconciled against the existing system before the next begins. This catches problems when they are small and reversible, not after the old system has been decommissioned.
What Migration May Include
- Legacy application migration across platforms
- Database migration and data conversion (DB2, SQL Server, PostgreSQL, Access, and others)
- ETL development for data extraction, transformation, and loading
- File format transformation and data mapping
- Validation and reconciliation between source and target systems
- Workflow migration — preserving business processes, not just data
- Interface and integration migration
- Reverse engineering undocumented behavior before change
- Vendor lock-in reduction through open standards and open-source adoption
- Phased cutover planning with rollback capability
Why Migrations Fail
Most migration failures happen because the project treats the existing system as disposable. Undocumented business rules get lost. Edge cases that the old system handled silently become production problems in the new one. Integrations that nobody mapped break on day one.
I have seen these patterns across decades of enterprise work. My job is to find those risks before the migration starts — through investigation, documentation, and conversation with the people who use the system every day.
Free Migration & Data Tools
Migration projects live or die on data validation and format conversion. These free browser-based tools handle the everyday extraction, reconciliation, and bridging tasks that come up repeatedly during a phased cutover — none of them require uploading your data to a server.
- Data Diff & Compare — reconcile source and target datasets phase by phase
- Data Profiler — understand source data before you decide how to transform it
- EBCDIC to ASCII Converter — decode IBM i and mainframe text exports
- Packed Decimal Converter — decode COMP-3, zoned, and overpunch numeric fields from legacy data
- COBOL Copybook Explorer — interpret record layouts from copybook definitions
- DDS ↔ SQL Converter — convert IBM i physical file definitions to SQL DDL and back
- Fixed-Width ↔ CSV — bridge positional legacy records to CSV
- Universal File Converter — switch between common tabular and text formats
Related Capabilities
Migration work often involves ETL and data pipelines, database development, and system integration. For organizations moving legacy interfaces to modern platforms, modernization may be part of the same engagement.
Further Reading
ETL: The Invisible Backbone of Enterprise Data — how data moves between systems during migration and why it matters.