Achasoft

Legacy App Migration

Safely migrate monoliths to modern stacks without downtime, data loss, or business disruption.

Your legacy system is a ticking clock.

That COBOL mainframe, that PHP 5 monolith, that Java 6 beast — they still run your business. But every day they accumulate more technical debt, more security vulnerabilities, and fewer developers willing to maintain them.

The real danger isn't the old technology — it's the risk of a botched migration. Rewrite projects fail at alarming rates, costing millions and years of lost momentum.

You need a migration strategy that's surgical, incremental, and risk-managed — one that keeps your business running while the transformation happens underneath.

migrate.sh
$ scan --legacy-stack
PHP 5.6 EOL 2018 ✗ unpatched
MySQL 5.5 EOL 2018 ✗ unpatched
jQuery 1.x EOL 2016 ⚠ 14 CVEs
Monolith: 380k LOC, 0 tests
$ migrate --strangler-fig
Phase 1 ✓ auth-service → Go + JWT
Phase 2 ✓ orders-service → Node.js
Phase 3 ✓ payments-service → Go
Phase 4 ✓ data layer → PostgreSQL 16
Phase 5 ✓ legacy retired → 0 downtime
$ _

The Strangler Fig approach.

Legacy System Audit

We reverse-engineer your existing system — mapping every dependency, data flow, integration point, and hidden business rule buried in the code.

Migration Strategy Design

We design the target architecture and choose the migration pattern — strangler fig, parallel run, branch by abstraction — based on your risk tolerance and timeline.

Data Migration Planning

Schema mapping, data transformation rules, and reconciliation testing. We ensure every record arrives intact with full audit trails.

Incremental Cutover

We migrate module by module, with rollback capabilities at every step. Traffic is shifted gradually with feature flags and canary deployments.

Validation & Decommission

Comprehensive regression testing, performance benchmarking, and parallel operation verification before the legacy system is retired.

Migration done right.

Zero-Downtime Migration

Your business runs uninterrupted while we transform the system underneath it.

Rollback at Every Step

Every migration phase has a tested rollback plan. If anything goes wrong, we revert instantly.

Data Integrity Guaranteed

Automated reconciliation ensures every record, every relationship, every constraint is preserved.

Modern Stack Benefits

Access modern tooling, cloud-native scaling, CI/CD, and a developer experience that attracts top talent.

Reduced Operational Risk

Eliminate EOL software, unpatched vulnerabilities, and the "bus factor" of scarce legacy expertise.

Cost Optimization

Modern infrastructure typically costs 40-70% less than legacy mainframe and on-premise hosting.

Migration toolkit.

Strangler Fig PatternAWS Migration HubDatabase Migration ServiceFeature FlagsCanary DeploymentsDockerKubernetesFlywayLiquibaseBlue-Green Deploy

What you receive.

Legacy System Audit Report

Complete dependency map, risk assessment, and technical debt inventory.

Migration Strategy Document

Phased plan with timelines, risk mitigation, and rollback procedures.

Data Migration Scripts & Validation Suite

Automated ETL pipelines with reconciliation testing framework.

Migrated Application on Modern Stack

Fully tested, deployed, and running on your target infrastructure.

Post-Migration Support & Monitoring

30-day hypercare period with 24/7 monitoring and incident response.

Ready to leave legacy behind?

Let's plan a migration that doesn't keep you up at night.

Start Your Migration Assessment