You will get a legacy code audit with a modernization roadmap & estimate
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Project details
Is your legacy .NET application slow, fragile, or expensive to change? I'll audit your codebase and hand you a
modernization roadmap with real cost and time estimates - before you commit to a rewrite.
I've spent 15+ years building and rescuing business-critical systems: ERP platforms, transport management systems, and internal tools running on .NET and Angular.
What you get:
• Full codebase and architecture review
• Dependency, security, and technical-debt report
• Prioritized roadmap - what to fix first, what to leave alone
• Realistic effort and cost estimate per phase
• A 60-minute walkthrough call
Most audits find a full rewrite isn't necessary. Targeted refactoring usually gets you 80% of the benefit at 20% of
the cost. You'll know which situation you're actually in.
You work directly with me. No account managers, no handoffs, no junior developer quietly assigned to your project.
Message me with your stack and rough codebase size, and I'll confirm scope before you order.
modernization roadmap with real cost and time estimates - before you commit to a rewrite.
I've spent 15+ years building and rescuing business-critical systems: ERP platforms, transport management systems, and internal tools running on .NET and Angular.
What you get:
• Full codebase and architecture review
• Dependency, security, and technical-debt report
• Prioritized roadmap - what to fix first, what to leave alone
• Realistic effort and cost estimate per phase
• A 60-minute walkthrough call
Most audits find a full rewrite isn't necessary. Targeted refactoring usually gets you 80% of the benefit at 20% of
the cost. You'll know which situation you're actually in.
You work directly with me. No account managers, no handoffs, no junior developer quietly assigned to your project.
Message me with your stack and rough codebase size, and I'll confirm scope before you order.
What's included
| Service Tiers |
Starter
$400
|
Standard
$900
|
Advanced
$1,800
|
|---|---|---|---|
| Delivery Time | 5 days | 7 days | 10 days |
Number of Revisions | 1 | 1 | 2 |
Design Customization | - | - | - |
Content Upload | - | - | - |
Responsive Design | - | - | - |
Source Code | - | - | - |
Optional add-ons
You can add these on the next page.
Fast Delivery
+$100 - $400
Additional Revision
+$100
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As always great to work this team, they have been invaluable over the past 6-7 years!
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Benjamin G.
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The team was fantastic. They consistently met deadlines, were easy to communicate with, and provided excellent flexibility and creative insight throughout the project.
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Rob H.
May 31, 2022
ASP .Net Zero (Angular and .Net Core) SPA in the Talent Analytics space: startup project
Serhii is and was an absolute pleasure to work with, he always understood the brief and made helpful recommendations throughout the project. Would definitely work with him again.
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Kyle P.
Jul 2, 2021
General Troubleshooting and Enchancements
Rocket Harbor has been a great team to work with over the last 4 years here at Logo Brands.
Our website was run on NopCommerce which no one in our company had much experience with. The team at Rocket Harbor was instrumental in helping us develop custom backend tools to make navigating and using the platform much easier.
If we ever needed something custom done to our website or needed an emergency fixe, Rocket Harbor was always quick to respond and did their jobs efficiently and affordably.
-Kyle Patterson: Senior Designer at Logo Brands
Our website was run on NopCommerce which no one in our company had much experience with. The team at Rocket Harbor was instrumental in helping us develop custom backend tools to make navigating and using the platform much easier.
If we ever needed something custom done to our website or needed an emergency fixe, Rocket Harbor was always quick to respond and did their jobs efficiently and affordably.
-Kyle Patterson: Senior Designer at Logo Brands
DT
Danielle T.
Sep 14, 2020
Looking for Full Stack Web developer with experience in Angular and .NET Core
I feel very confident that if you hire them they will do an amazing job
About Serhii
.NET Developer | Legacy Migration & Modernization | C#, ASP.NET Core
100%
Job Success
Lviv, Ukraine - 2:50 pm local time
Most of my work starts the same way: a system that still runs the business but has become expensive to change. Deployments are fragile, nobody wants to touch the data layer, and the original developers are gone. I assess what's actually there, tell you what's worth keeping, and migrate it in stages you can ship — not a rewrite you wait two years for.
How I approach migration
Strangler pattern over big-bang rewrites: new functionality goes into ASP.NET Core behind the existing surface while the legacy system keeps running. Domain extraction and data-layer replacement before UI work, so behavior stays verifiable. Parallel-run validation against the legacy system on every cutover.
Legacy stacks I work with: .NET Framework 3.5 through 4.8, ASP.NET WebForms, ASP.NET MVC, WinForms and WPF, VB6, classic ADO/ADO.NET, and SQL Server backends built around stored procedures.
Multi-tenant SaaS and ABP
Roughly 9,800 production hours on multi-tenant platforms built with AspNetZero and the ABP Framework — tenant isolation, module boundaries, permission systems, upgrade paths. AspNetZero is nearing end of life, and the ABP Framework is where that ecosystem is heading. If you're running AspNetZero or ASP.NET Boilerplate, migrating to ABP is work I know from the inside rather than from documentation.
ERP, TMS and platform work
Custom API and integration engineering across ERP, TMS and SaaS platforms — REST APIs in ASP.NET Core, background workers, EDI, and integrations against CRM, payment, accounting and carrier systems. Authentication with JWT, OAuth and Azure AD.
Angular and React front ends on ASP.NET Core backends: admin dashboards, operational tooling, reporting and role-based access for ERP, TMS and SaaS products.
Warehouse and inventory systems: stock movement, barcode scanning, purchase orders, cycle counts, and the mobile clients that go with them.
Azure and AWS deployment, CI/CD pipelines, monitoring, logging, and cost-aware infrastructure. Azure AI and LLM integration where it earns its place — search, summarization, classification, and Slack or Teams workflow bots.
Track record on Upwork: 11,437 hours, $400K+ billed, 100% Job Success across 22 contracts. The longest ran seven years and 8,440 hours on a single multi-tenant platform.
How engagements run: I do the engineering myself and stay the technical owner and point of contact throughout. When scope needs mobile, UI/UX, QA or DevOps specialists, I bring in people I've worked with for years rather than handing you to a project manager.
If you'd rather start with something fixed-scope, the projects below cover the usual entry points — a legacy code audit with a modernization roadmap and estimate, a custom API integration, an Angular admin dashboard, or ongoing support for an existing .NET system.
Steps for completing your project
After purchasing the project, send requirements so Serhii can start the project.
Delivery time starts when Serhii receives requirements from you.
Serhii works on your project following the steps below.
Revisions may occur after the delivery date.
Scope & access setup
Share repo access or a codebase archive. We confirm scope, discuss confidentiality, and agree on audit depth.
Codebase & architecture review
Full analysis of structure, dependencies, code quality, security exposure, and technical debt.