Stabilize: Legacy stack assessment and risk mapping
Full estate assessment, risk and dependency mapping, and target state definition. Establish the baseline before any transformation begins
Agentic legacy modernization
Overview
Legacy applications are doing more than slowing you down — they're actively blocking the AI opportunity. Four compounding pressures are making inaction increasingly costly.
- ~60% AI is blocked by old technology
- ~3× new products launch slower
- 60–80% upkeep drains the budget
- 40–50% old systems invite security risk
This is the right time to modernize. The agentic AI opportunity is here, but AI-led process change cannot scale until the underlying technology stack is ready. Traditional modernization programs are often slowed by manual discovery, incomplete application maps, operational risk, long timelines, and scarce legacy specialists.
Sonata’s agentic legacy modernization approach changes this model. Using its Frontier Workbench, Sonata combines human judgment, AI agents, and an end-to-end modernization platform to transform monolithic applications, fragmented data, undocumented business rules, legacy code, manual operations, and tribal knowledge into modular, AI-ready, cloud-native architecture.
Our approach
Digitize: Spec-driven engineering and cloud-native re-platforming
Agentic reverse engineering auto-generates specs. Cloud-native re-platforming and data estate modernization follow structured, auditable paths
Intelligize: Harmoni.AI™ intelligence layer and AI-infused workflows
AI capabilities are embedded directly into modernized workflows — not bolted on after the fact
Autonomize: Governed, autonomous execution via AgentBridgeTM
Multi-agent orchestration with full governance controls — every action traceable, every decision auditable
OFFERINGS
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Agentic reverse and forward engineering
Re-platform legacy applications to modern technology stacks through AI agents that assess, reverse-engineer specificationsRe-platform legacy applications to modern technology stacks through AI agents that assess, reverse-engineer specifications, forward-engineer code, test, and deploy Modernization path: Legacy tech stack → Modern tech stack
Powered by: Sonata Frontier Workbench, Sonata Migration Agents & Skills, Harmoni.AI Proven outcomes: 0 security defects post modernization; workflow solution rewritten from scratch in 4 months
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Agentic .NET upgrades on AWS and Azure
Modernize legacy .NET applications through an 8-step agentic upgrade process using proven Microsoft and AWS upgrade toolingModernize legacy .NET applications through an 8-step agentic upgrade process using proven Microsoft and AWS upgrade tooling
Modernization path: .NET 4.x → .NET 8 LTS
Powered by: Sonata Frontier Workbench, Sonata Migration Agents & Skills, Harmoni.AI
Proven outcomes: 5x request throughput; 39 projects migrated with zero release impact
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Agentic Hybris modernization
Lift commerce logic out of SAP custom code into open services with AI-led analysis of pricing, cartLift commerce logic out of SAP custom code into open services with AI-led analysis of pricing, cart, and checkout logic. Sonata enables any-to-any modernization with no vendor lock-in
Modernization path: SAP Hybris → Composable builds
Powered by: Sonata Frontier Workbench, Business Analysis Agent, CMS Migration Agent
Proven outcomes: 60% faster take-out; multi-region platforms decoupled in 6 month
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OutSystems transformation
Reverse-engineer low-code monoliths onto a modern cloud stack with free discoveryReverse-engineer low-code monoliths onto a modern cloud stack with free discovery, scoring, roadmap creation, and dedicated OutSystems migration bots
Modernization path: OutSystems → React + .NET
Powered by: Sonata Frontier Workbench, Harmoni.AI, AI Mentor Studio
Proven outcomes: 2x feature velocity; 34% lower run cost across 75+ modules
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WinForms to React
Re-engineer desktop forms into modern single-page applications using Copilot-assistedRe-engineer desktop forms into modern single-page applications using Copilot-assisted
React generation and standardized migration, testing, and deployment templates
Modernization path: WinForms → React SPA
Powered by: Sonata Frontier Workbench, Sonata Figma → React Generator, IntellQA
Proven outcomes: More than 90% automated test coverage; approximately 50% faster delivery
Sonata Advantage
Proprietary Frontier Platform and workbench
End-to-end tooling covering apps, data, and architecture – not a patchwork of third-party tools
Human + agents + platform model
Engineers govern strategy; agents handle execution. The win is more modernization – better, faster, cheaper
100% auditable Agent execution
Every agent action logged and traceable. Governance built in from day one, not added later
Outcome-linked commercial models
Flexible engagements that tie investment directly to measurable business results
Success Stories
Mortgage meets modern .NET
Sonata partnered with a leading U.S.-based mortgage lender and servicer to modernize its legacy loans platform. By leveraging Amazon Q, AWS Transform, GitHub Copilot and Generative AI, Sonata delivered a seamless upgrade from .NET 4.x to .NET 8.0, resulting in 30% savings in time and effort, up to 5x performance gains and enhanced scalability and maintainability through modern architecture.
.NET for Legal
Sonata helped a leading software solutions company modernize their enterprise legal management (ELM) product by upgrading to the latest .NET framework using Spec Driven Development on Github Copilot. This resulted in up to 5x improved request throughput, 30–50% lower memory usage and enabled cross-platform deployment, leading to reduced hosting costs and enhanced scalability
.Net done right
Enabled a tech company to modernize and streamline over 180 legacy applications by migrating from .NET Framework 4.8 to .NET Standard 2.0, leveraging GenAI. This strategic transformation led to performance boosts of up to 20x and unlocked potential cost savings of up to 20% in COGS.
.NET 8 modernization to deliver faster migration
Sonata Software partnered with the client and AWS to leverage Amazon Q Developer and Amazon Transform, two AI-powered services designed to accelerate software modernization and enhance developer efficiency.