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Service · LEGACY MODERNIZATION

Legacy Modernization, for systems your business still depends on.

Assess outdated, complex systems and modernize them into a maintainable, scalable, and secure IT foundation - from current-system inventory and planning to migration, rebuild, and long-term operation.

ASSESSMENT
Inventory first
systems, code, data, operation
RISK CONTROL
Phased plan
avoid forced big-bang renewal
APPROACH
5 options
rehost / replatform / refactor / rebuild / replace
GOAL
DX-ready
maintainable, scalable, secure
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Common questions about this service:
What is the typical team composition?How do you handle IP and security?Can I meet engineers before signing?What if I want to scale up or down?

WHY MODERNIZATION NOW

A legacy system is not just old. It is a system that blocks change.

Many enterprise systems continue to run important business operations for years. The problem starts when the system becomes too complex to maintain, too risky to secure, or too expensive to change.

Older languages and frameworks

Systems built in COBOL, VB6, or outdated frameworks may become difficult to maintain as available engineers decrease.

Unsupported operating systems

When OS or middleware support ends, security and compliance risks increase.

Operations depend on specific individuals

Business continuity becomes fragile when only a few people understand the system.

High operating cost

Maintenance, infrastructure, manual operation, and change requests become increasingly expensive.

DX becomes harder

Old architecture can prevent API integration, cloud adoption, data utilization, automation, and AI use cases.

HOW IT WORKS · 4 STEPS

01 · Inventory & assessment

Review current systems, languages, OS, architecture, data, dependencies, operation process, and business-critical functions.

02 · Strategy selection

Decide whether to rehost, replatform, refactor, rebuild, or replace based on risk, budget, timeline, and business impact.

03 · Phased execution

Migrate, rebuild, or renew by priority so business operation can continue while the IT foundation is improved.

04 · Stabilize & operate

Validate quality, improve documentation, reduce dependency on specific individuals, and support long-term operation.

Not sure which modernization path fits your system?

Start with a discussion. We will listen to your current situation and help identify the practical next step.

View case studies Book a consult

WHAT LEGACY MODERNIZATION MEANS AT SYP

Updating old systems into an IT foundation for sustainable growth

SYP’s Legacy Modernization Support helps companies update and optimize old IT systems with modern technologies and architectures. The goal is not simply to move systems from one environment to another, but to create an IT foundation that is easier to maintain, scale, secure, and improve over time.

SYP works with clients from current-state inventory and assessment through modernization planning, migration, development, testing, deployment, and operation.

Discuss your legacy system →

COMMON MODERNIZATION TRIGGERS

Common situations we help clarify

“The system still works, but every change takes too long.”

“The original specifications are missing or outdated.”

“Only one or two people understand the operation.”

“The OS or middleware is no longer supported.”

“We want to use cloud, data, or AI, but the current system blocks us.”

“We know modernization is necessary, but a full rebuild feels too risky.”

FOUR CORE OBJECTIVES

Modernization should improve the system you operate - and the options you have next.

Maintainability

Make the system easier to understand, change, test, and hand over.

Scalability

Prepare the architecture and infrastructure for future business growth.

Security

Reduce risks from unsupported environments, outdated dependencies, and unclear access control.

DX readiness

Enable future integration, automation, data use, cloud adoption, and AI-related workflows.

MODERNIZATION APPROACHES

Five paths. The right one depends on your risk, budget, timeline, and business goal.

Modernization does not always mean rebuilding everything. We assess where each approach makes practical sense.

Approach Overview Features / when it fits
Rehost Move the application as-is to cloud infrastructure. Also called Lift & Shift. Useful when the first priority is infrastructure renewal with minimal application change.
Replatform Make minor changes while migrating to cloud or a new OS. A balanced option when cost, speed, and benefit must be controlled.
Refactor Redesign code and structure. Improves the application and helps eliminate technical debt.
Rebuild Reconstruct the application from scratch. Suitable for DX-oriented renewal, but cost and scope are higher.
Replace Swap with packaged software or SaaS. Prioritizes speed and business process optimization when custom development is not the best answer.

DELIVERY SCOPE

From assessment to execution

  • System inventory and current-state assessment
  • Technical debt and risk analysis
  • Modernization roadmap and cost / timeline planning
  • Architecture design and migration strategy
  • Cloud migration / OS migration planning
  • Refactoring, rebuild, or package/SaaS replacement support
  • Data migration and integration design
  • Testing, deployment, and post-release stabilization
  • Documentation recovery and operation handover
  • Long-term maintenance and improvement

TEAM & GOVERNANCE

Modernization needs both business context and engineering control

Role Responsibility
Business Consultant / BAClarifies goals, operations, hidden business rules, and user impact.
Solution ArchitectDesigns target architecture and modernization strategy.
Tech LeadReviews existing code and technical constraints.
EngineersImplement migration, refactoring, rebuilding, integration, and UI/API renewal.
QA EngineersValidate functional behavior, regression impact, data integrity, and release readiness.
DevOps / Cloud EngineerSupports infrastructure, deployment, monitoring, and cloud readiness.
PM / Bridge PMManages timeline, communication, reporting, and phased release governance.

CUSTOMER VOICE

What clients value in the working relationship

Communication quality, understanding of requirements, stability, and follow-through.

Beyond the high quality, we really feel the speed of development. Deadlines are strictly met, and high quality is maintained.

Mr. Junpei Suzuki - Product Manager
SpiderPlus & Co.

SYP places strong emphasis on quality and has established robust quality assurance processes. As a result, we can confidently entrust them with end-to-end system development.

Mr. Kimihiko Asabe

Deputy Division Manager, DX Platform Division · Nomura Research Institute (NRI)

SY Partners has committed to ensuring that their customers always receive high-quality IT products that meet all technical requirements. We have collaborated with SY Partners on many IT projects and have always been satisfied with the products and services they provide.

Ms. Usui Kiki

CEO · Hubbit, Inc.

We have collaborated with SY Partners on a software development project and were very impressed with the professionalism and dedication of their technical team.

Mr. Takuya Kubota

Co-Founder CTO · mui Lab, Inc.

The quality of service provided by SY Partners is truly remarkable. They always ensure that all of our requests are met on time and with the best quality possible.

Mr. Satoshi Kosugi

CEO · Overture Inc.

Read customer interviews →

FULL WORKFLOW · 7 STEPS

From business consulting to maintenance / operation

Legacy modernization often starts with unclear information. A structured workflow helps turn current-system risk into a practical renewal plan.

Step Description
Step 01
Business Consulting
Conduct research to understand the client’s business goals and operations, study the market, and identify important factors in order to propose suitable solutions.
Step 02
Requirement Definition
Define software requirements, key features, functions, and technical conditions so the product can meet real customer needs.
Step 03
Designing
Identify the software architecture, core components, and user interface. Ensure the product is scalable, upgradable, and secure.
Step 04
Development
Build the product based on the agreed requirements and design blueprint, using appropriate technologies and tools to produce a high-quality result.
Step 05
Testing
Ensure the software meets requirements and works accurately. QA specialists perform rigorous testing and fix issues when necessary.
Step 06
Deployment
Install, configure, and test the product before and after it is deployed in the real application environment.
Step 07
Maintenance / Operation
Maintain and operate the product to ensure stability and improve or upgrade it when necessary.

FAQ

Questions we hear before modernization starts

Which modernization approach is right for us?

SYP starts with inventory and assessment, then recommends the appropriate path: Rehost, Replatform, Refactor, Rebuild, or Replace.

Is Lift & Shift enough?

It can be useful when the first priority is infrastructure renewal, but it may not solve technical debt or maintainability. SYP should help judge whether it is enough for the business goal.

Can SYP support COBOL or VB6-related modernization?

SYP can assess systems using older languages such as COBOL or VB6 and help plan a practical modernization path. Final technical scope should be confirmed case by case.

Can modernization reduce security risk?

Yes. Modernization can help reduce risks from unsupported OS, outdated dependencies, unclear access control, and old operation processes.

Do we need to rebuild everything?

No. Depending on the situation, modernization may mean rehosting, replatforming, refactoring, rebuilding selected functions, or replacing parts with packaged software/SaaS.

What would modernization cost?

Cost depends on system size, risk, migration approach, and release scope. The first step should be assessment and roadmap creation.

Start with one workflow worth improving.

Tell us what process you want to automate, assist, or make easier to operate. We will help clarify the use case, data, system integration, and first practical release.

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