From Feature Hooks to TanStack Query: How we helped Forward Financing Make the Switch

Feature hooks typically combine React's built-in hooks to manage API calls within custom hooks. While this pattern provides some organization and reusability, it comes with significant limitations that become apparent as applications scale.

1. No Intelligent Caching

Traditional feature hooks treat each API call as an isolated event. Every time a component mounts, it makes a fresh network request, even if identical data was just fetched by another component. This leads to unnecessary bandwidth usage, slower user experiences, and increased server load. Developers often end up implementing their own caching solutions, which adds complexity and potential for bugs.

2. Manual State Management Overhead

With feature hooks, developers must manually orchestrate multiple state variables for loading states, error handling, and data storage. This becomes exponentially more complex when dealing with different types of loading states—initial loading versus background refetching, for example. The boilerplate code quickly accumulates, making components harder to read and maintain.

3. Static Data Problem

Once data is fetched through a traditional feature hook, it remains static until the component unmounts and remounts or until you manually trigger a refetch. There's no built-in mechanism to keep data fresh or to update it when certain conditions are met, such as when the user returns to the application or when network connectivity is restored.

4. Complex Error Scenarios

Error handling in feature hooks requires manual state management and often lacks sophistication. Implementing retry logic, exponential backoff, or different error handling strategies for different types of failures requires substantial additional code. Most implementations end up with basic error states that don't provide the resilience users expect from modern applications.

TanStack Query gives you declarative, always-up-to-date auto-managed queries and mutations that directly improve both your developer and user experiences. Rather than thinking about individual API calls, TanStack Query treats server state as a distinct category of state that requires specialized handling.

The fundamental insight behind TanStack Query is that server state has unique characteristics that differentiate it from client state. Server state is persisted remotely, can become stale, can be updated by other users or processes, and requires asynchronous operations to access. Traditional state management approaches don't account for these characteristics effectively.

1. Intelligent Caching System

TanStack Query offers a more scalable, feature-rich approach to data fetching that handles caching, retries, background refetching, and pagination—things that would require a lot of extra work if you were doing it all with custom hooks. The library automatically caches your data using a sophisticated key-based system that shares data across components intelligently.

When multiple components need the same data, TanStack Query ensures only one network request is made, with all components receiving the cached result. The cache is automatically managed with sensible defaults for cache times and stale times, but provides granular control when needed. This eliminates the redundant API calls that plague feature hook implementations.

2. Automatic Background Synchronization

TanStack Query automatically keeps your data fresh through background refetching. It intelligently refetches data when the browser window regains focus, when network connectivity is restored, or at configurable intervals. This ensures users always see current data without requiring manual refresh actions or complex polling implementations.

The library distinguishes between different types of loading states—initial loading when there's no cached data versus background loading when updating existing data. This allows for sophisticated UI patterns where users can continue interacting with cached data while fresh data loads in the background.

3. Sophisticated State Management

Rather than managing multiple boolean flags for different states, TanStack Query provides a rich state model that accurately represents the various states of server data. You get clear distinctions between pending states (no data yet), error states, success states, and fetching states (background updates).

This granular state information enables more nuanced user interfaces. For example, you can show a full loading spinner for initial loads while displaying a subtle indicator for background updates, providing users with appropriate feedback for different scenarios.

4. Robust Error Handling and Recovery

TanStack Query includes built-in retry logic with exponential backoff for failed requests. The library can differentiate between different types of errors and apply appropriate retry strategies. Network errors might be retried automatically, while authentication errors might not be.

The error handling system is designed to be resilient and user-friendly, automatically recovering from temporary network issues without requiring user intervention. This creates a more polished user experience compared to the basic error handling typically found in feature hook implementations.

5. DevTools and Debugging

TanStack Query includes comprehensive developer tools that provide visibility into cache states, query lifecycles, and network activity. This debugging capability is invaluable for understanding and optimizing data flow in complex applications—something that's difficult to achieve with custom feature hooks.

Beyond the technical improvements, TanStack Query significantly enhances the developer experience. You will be surprised at how little code you're writing or how much code you're deleting when you use TanStack Query. The declarative API reduces boilerplate code substantially, making components cleaner and easier to understand.

The library's extensive TypeScript support provides excellent autocomplete and type safety, reducing runtime errors and improving development velocity. The consistent patterns across different types of queries and mutations create a predictable development experience that scales well across large teams.

The evolution from feature hooks to TanStack Query represents a maturation in how we think about server state management in React applications. While feature hooks served as a stepping stone from basic useEffect patterns, TanStack Query provides the sophisticated infrastructure that modern applications require.

Forward Financing is so happy with the implementation of TanStack, we will start incorporating it into other applications as well. 

The investment in learning TanStack Query pays dividends in reduced development time, fewer bugs, and better user experiences. As your applications grow in complexity, you'll appreciate having a robust foundation for server state management rather than building and maintaining custom solutions.