Legacy software modernization services for the codebase your team has outgrown. We re-engineer it into code your engineers can own and extend. The price gets fixed once the audit maps the full scope.
Audit defines fixed scope
Your team owns the result
Rollback path stays live
Legacy System Audit
We trace the codebase, the data model, and the integration points before any code changes happen. You get a rebuild plan grounded in what the system does in practice, apart from any old documentation.
Application Re-Engineering
Application re-engineering covers each module in turn, rewriting onto a current runtime. Characterization tests hold the new code to the legacy system's exact behavior until your engineers take over.
Monolith-to-Microservices Refactoring
Services get exposed through an API gateway one at a time, following the strangler fig pattern across the migration. The result is a codebase of independently deployable units your team controls.
Cloud Migration Engineering
Workloads move onto cloud infrastructure configured for autoscaling and monitoring. Cloud migration for legacy systems reduces the operational overhead your engineers would otherwise carry manually.
Database & Data-Layer Modernization
The data model separates from the application logic built around it over the years. Double-write keeps both databases in sync, and integrity checks compare them before reads switch over at cutover.
API & Integration Modernization
We replace point-to-point connections with REST or GraphQL endpoints partners and internal tools can use directly. A new integration that once took several months now fits into a regular delivery cycle.
UI / UX Modernization Development
Interfaces get rebuilt on a current frontend framework. Your team keeps the underlying workflows familiar to the people using them daily, which keeps training overhead low through the transition.
Security & Compliance Hardening
We map SOC 2, HIPAA, or PCI-DSS controls onto the target architecture as the rebuild proceeds, closing gaps that would need a partial legacy rewrite. Your auditors keep the final say on certification.
Post-Modernization Support
Once the system is live, SapientPro stays available for new features and the modernization work that comes next. Your developers receive full documentation, keeping them in control of the system.
GET A SCOPE AND A START DATE
Send over the codebase and a short list of integrations to start the legacy software modernization services audit. What follows is a detailed scope with fixed milestones and a firm price, before any development starts.

01
Hiring for Your Stack Has Dried Up
The talent pool that supported your codebase a decade ago has thinned out, and that's only half the problem. The senior engineers still on the market actively avoid outdated framework versions on their CV, so each hire takes months to close and the salary band keeps moving up.
02
Every Integration Costs Three Months
A new partner, payment provider, or analytics tool should connect within a sprint. Legacy code that speaks neither REST nor GraphQL turns each connection into its own custom build, repeating the plumbing and pushing features down the backlog.
03
Your AI Roadmap Hits the Data Layer
RAG pipelines, agents, and analytics need a data model they can query directly and reliably. A schema fused inside a legacy monolith stalls every AI initiative at the same point, weeks spent untangling data access before any model gets trained.
04
The System Outgrew Its Last Owner
Legacy codebases that arrive through an acquisition, or survive a founding engineer's departure, carry decisions nobody documented or logic nobody can explain. Each change becomes an experiment, the people who knew the intent left years before.
05
Compliance Moved Under Your Feet
SOC 2, HIPAA, PCI-DSS, and GDPR keep tightening, and architectures that predate strict enforcement of these controls tend to fall short of what auditors now expect. Bolting them onto the legacy system creates new gaps, a rewrite closes them.
06
A Rewrite Started and Stalled
An internal team began migrating to a new stack. Priorities shifted, engineers moved on, and the scope grew well past what anyone had budgeted. Half the system runs on legacy code, half on new, and velocity has dropped below where it started.
Product CTOs
A CTO whose product roadmap keeps colliding with a legacy codebase, one built before AI features, modern integration protocols, and compliance requirements found their way onto every planning cycle.
SaaS Founders
The original team is gone, the legacy codebase has aged past its support window, and customers keep asking for features that strain an architecture already running close to its limit on every front.
Retail Operators
Custom e-commerce or operations platforms paired with ageing ERP systems, where every partner integration becomes its own project instead of a routine configuration change.
Fintech and Health
A CTO in a regulated industry whose legacy system was built before the current SOC 2, HIPAA, PCI-DSS, or GDPR bar, leaving the architecture short of what auditors and regulators now require from it.
Six steps, each with a defined output your team can verify. The audit sets the scope, characterization tests hold the rewrite to the legacy system's behavior, and incremental cutover keeps production live until the last module moves.
Sprinkle
How Sprinkle Cut Costs by 50% and Expanded User Base by 75,000 Through Strategic Optimization
We migrated Thailand's largest water delivery CRM to a custom solution, automating the call center and optimizing order management.
Footshop
Footshop Webstore Overhaul Case Study
SapientPro rebuilt Footshop’s store, added multi-currency payments, and deployed AWS multi-region hosting to keep the site fast across Europe.
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GPS Platform Upgrade with 30% Subscription Growth
We helped MasTrack rebuild its tracking platform, added real-time features, and automated billing, leading to faster user handling and 30% subscription growth.
ChatGPT
A conversational AI developed by OpenAI that specializes in generating human-like responses, facilitating engaging and contextually relevant dialogues.
01
Production Code as the Deliverable
Each legacy application modernization engagement concludes with a working system in your production environment, documented and ready for your team to extend. The output is the codebase itself, the system you will run and own going forward.
02
A Fixed Price, Set After the Audit
The audit precedes the quote in legacy system modernization services. Once the codebase, data model, and all integrations are mapped, we set a fixed price and a milestone plan. A codebase more complex than indicated remains our cost to absorb.
03
Direct Experience With Your Stack
Most legacy codebases we see have the same problems underneath. A framework that stopped getting updates two versions ago. A frontend the team avoids. An ERP tangled into the application layer. We've seen those patterns enough times to spot them in the audit.
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