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Migration Service

From Legacy VBA to Office Web Add-ins

We transform your fragile Excel and Word macros into cross-platform Office Web Add-ins. By moving your business logic to secure C# and TypeScript, your tools will run flawlessly on desktop and web browsers. Everything is deployed centrally through Microsoft 365, completely eliminating local files.

Coverage

What We Migrate

VBA Macros (Excel & Word)

Procedures, modules, and shared libraries translated into structured TypeScript with clear boundaries.

Ribbon Customizations

RibbonX and command UI rebuilt with a fresh modern look using the Office.js ribbon and manifest model.

Task Panes & UserForms

Legacy UI patterns re-implemented as task panes and HTML dialogs that behave consistently across hosts.

COM Add-ins

Desktop COM integrations assessed and replaced with supported web-friendly APIs and services where needed.

Data Connections

Queries and local database connections rebuilt and upgraded to secure REST APIs to ensure reliable data flow.

Functionality & Business Logic

Complex calculations and User-Defined Functions rebuilt as modern, natively integrated custom functions using Office.js.

Deliverables

What You Get

  • Complete Add-in Source Code

    You receive the fully editable TypeScript, HTML, and CSS source code. You retain 100% ownership of the frontend product, giving you the freedom to manage it internally or partner with us for ongoing feature development.

  • Production-Ready C# Backend

    A high-performance backend application built in C# (ASP.NET). It extracts complex business logic, database operations, and external integrations out of the fragile Office document, increasing both processing speed and data security.

  • Infrastructure & Hosting Guidance

    To ensure maximum security and data compliance, the solution is deployed entirely within your environment. We provide step-by-step architectural guidance for your servers, databases, and the exact Microsoft Entra ID App Registration blueprints needed for secure SSO.

  • CI/CD Pipelines & Version Control

    We configure automated deployment pipelines and establish a clean Git repository history in Azure DevOps. This ensures your team can safely push changes or roll back to the stable baseline delivery if internal mistakes occur.

  • Documentation & Handover Session

    Upon project completion and sign-off, we provide extensive technical documentation of the stable baseline architecture. We conclude with a live handover session, shifting ongoing support to your team or transitioning into an active retainer agreement.

Why modernize

Why Office.js Over VBA

Cross-Platform Compatibility

Office Add-ins run identically across Windows, Mac, and Office Online. You no longer have to maintain separate codebases or deal with VBA breaking when a user switches to a different operating system or browser.

Zero Local Installation

Modern add-ins are deployed centrally via the Microsoft 365 Admin Center. Users get immediate access to the latest features without IT ever having to push local files, register DLLs, or update desktop registries.

True Version Control

Source code is decoupled from the document. This allows your team to use standard Git workflows, enforce code reviews, and execute safe rollbacks, completely eliminating the risk of corrupted, untrackable macro-enabled files.

Microsoft's Official Path

VBA is a legacy technology increasingly restricted by enterprise security policies. Office.js is Microsoft's actively developed, cloud-native standard for secure business automation and the definitive future of the platform.

Office.js is actively developed by Microsoft and handles the vast majority of legacy Excel and Word operations. For the rare edge cases where a direct API equivalent doesn't yet exist, we identify them during the initial analysis and architect the most secure path forward, whether through custom backend logic, a phased migration, or a supported hybrid approach.

Engagement

How It Works

From analysis to handover, structured to keep your business running.

  1. 1

    Discovery & Analysis

    We begin by mapping your entire VBA ecosystem. We identify legacy dependencies, document critical business logic, and pinpoint security vulnerabilities. This deep dive allows us to architect a modern, scalable backend and UI strategy that perfectly aligns with your existing workflows.

  2. 2

    Roadmap & Pricing

    Based on our analysis, we provide a comprehensive technical proposal. You receive a clear architectural blueprint, a phased deployment timeline, and a firm fixed price. There are no hidden fees or surprise hourly overages. You know exactly what it costs to modernize.

  3. 3

    Parallel Development

    We provide the exact Microsoft Entra ID blueprints upfront so your IT team can provision a secure sandbox. We then build your new architecture incrementally in the background. Your legacy VBA remains fully functional while you receive regular progress demos.

  4. 4

    Testing & Deployment

    Before going live, we run the new web add-ins alongside your old macros using your real business data to validate computational accuracy. Once UAT sign-off is complete, we guide your IT team through a centralized Microsoft 365 rollout.

  5. 5

    Ongoing Support & Retainers

    Following the live deployment and technical handover session, we provide an initial 3-month warranty period to ensure absolute stability in production. From there, you can transition into a dedicated retainer agreement for continuous maintenance, priority support, and future enhancements.

FAQ

Common Questions

Ready to REVAMP?

Send us a message or Book a free 30-minute discovery call.

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