A Simple Technique to Break Free from Vendor Lock-In: Technology-Agnostic Design Pattern

If you’ve ever built an app that talks to some external service, you know how painful it can be when the business team suddenly says: “Hey, we need to change our technology from ChatGPT API to Claude API”. That usually means ripping apart half your codebase just to swap a library. Not fun. That’s where technology-agnostic design patterns come in. The idea is simple: keep your business logic (the what) separate from the technology-specific implementation (the how).

When building software systems, developers often face the challenge of keeping business logic clean and adaptable while integrating with ever-changing technologies. Technology-agnostic design patterns allow us to separate core business logic from technology-specific implementations. This ensures maintainability, testability, and flexibility to evolve the system without rewriting large portions of code.

One such approach is the Manager-Provider pattern. This pattern is particularly useful when the system must support different underlying providers (e.g., database engines, cloud services, payment gateways) while keeping the higher-level logic independent of those implementations.

Use Case Example

Imagine you are building a file storage service. The business requirements are simple:

• Users can upload and download files.

• Files should be stored reliably.

The implementation, however, could vary:

• Store files in local disk for development/testing.

• Store files in Amazon S3 for production.

• Store files in Azure Blob Storage for enterprise clients.

Without a technology-agnostic approach, you might tightly couple your business logic to one provider, making future changes costly and error-prone.

Importance of Technology-Agnostic Design Patterns

1. Flexibility – Swap providers without rewriting business logic.

2. Testability – Mock providers for unit tests without needing actual external services.

3. Maintainability – Clear separation of responsibilities.

4. Scalability – Add new providers with minimal effort.

Dependency Injection (DI) Concept

At the core of this pattern is Dependency Injection (DI). Instead of hardcoding dependencies, you inject them at runtime. The business logic depends on an abstraction (e.g., an interface), while the concrete implementation is provided by configuration or runtime binding.

Example:

// Abstraction
public interface IStorageProvider
{
     void Upload(string fileName, Stream content);
    Stream Download(string fileName);
}

// Business Logic depends on abstraction
public class FileManager
{
    private readonly IStorageProvider _provider;

    public FileManager(IStorageProvider provider)
    {
        _provider = provider;
    }

    public void SaveFile(string fileName, Stream content)
    {
         _provider.Upload(fileName, content);
    }

    public Stream GetFile(string fileName)
    {
          return _provider.Download(fileName);
    }
}

Separation of Business Logic and Technology-Specifics

The FileManager class contains the business logic (file handling) without knowing where the files are stored. Technology-specific providers handle actual storage details.

// Local File Implementation
public class LocalFileStorageProvider : IStorageProvider
{
     public void Upload(string fileName, Stream content)
     {
          using var fileStream = File.Create(fileName);
          content.CopyTo(fileStream);
     }

     public Stream Download(string fileName)
     {
          return File.OpenRead(fileName);
     }
}

// AWS S3 Implementation (simplified)
public class S3StorageProvider : IStorageProvider
{
     public void Upload(string fileName, Stream content)
     {
          // Call AWS SDK
     }

     public Stream Download(string fileName)
     {
          // Call AWS SDK
          return new MemoryStream();
     }
}

Techniques for Implementation

1. Configuration-Based Provider Selection

   • Define provider type in configuration (e.g., appsettings.json, YAML).

   • Use a factory to instantiate the correct provider at runtime.

2. Switchable Providers at Runtime

   • Useful for multi-tenant systems.

   • Example: Tenant A uses LocalFileStorage, Tenant B uses S3.

3. Plug-in or Strategy Pattern

   • Allow new providers to be registered dynamically without modifying core code.

Example: Configuration-Based Manager-Provider Pattern 

public class StorageProviderFactory
{
     public static IStorageProvider CreateProvider(string providerType)
    {
        return providerType switch
        {
            "Local" => new LocalFileStorageProvider(),
            "S3" => new S3StorageProvider(),
            _ => throw new ArgumentException("Invalid provider type")
        };
    }
}

// Usage
string providerType = "S3"; // From config
IStorageProvider provider = StorageProviderFactory.CreateProvider(providerType);
FileManager manager = new FileManager(provider);

Conclusion

The Manager-Provider pattern exemplifies the benefits of technology-agnostic design. By leveraging dependency injection, configuration, and provider abstraction, we can:

• Keep business logic clean.

• Easily swap or extend providers.

• Build resilient, flexible, and future-proof systems.

In today’s rapidly evolving technology landscape, adopting such patterns is not just a good practice—it’s a necessity.