SPFx 1.24 React 18: Migrating SharePoint Framework Solutions Safely

SharePoint Framework (SPFx) solutions often depend on a specific combination of Node.js, TypeScript, React, build tooling, and Microsoft 365 APIs. When the framework version changes, upgrading only the package version is rarely enough.

A migration can affect:

• React components

• TypeScript compilation

• Web part lifecycle behavior

• Third-party dependencies

• Build and packaging commands

• SharePoint APIs

• Existing custom controls

• Automated tests

SPFx 1.24 introduces a modernized development baseline that makes React 18 compatibility an important consideration for existing solutions.

The safest migration strategy is to treat the upgrade as a controlled compatibility exercise, rather than simply replacing package versions.

Why SPFx Migration Requires Planning

A typical SPFx application has several interconnected layers:

SPFx Solution
    |
    +---- React Components
    |
    +---- TypeScript
    |
    +---- Build Toolchain
    |
    +---- Microsoft 365 APIs
    |
    +---- Third-Party Packages
    |
    +---- Deployment Package

Changing the framework version can affect several of these layers simultaneously.

A successful build does not necessarily mean the migration is complete.

For example:

Build
  ↓
Successful

Runtime
  ↓
Component Error

Production
  ↓
User Impact

Therefore, migration validation must include both build-time and runtime testing.

Understand the Existing Project First

Before changing dependencies, inspect the existing project.

Important files include:

package.json
config/package-solution.json
config/serve.json
tsconfig.json
gulpfile.js
src/

Start by identifying the current versions:

node --version
npm --version
gulp --version

Then inspect the project's dependencies:

npm list --depth=0

This provides a baseline before making changes.

Create a Migration Branch

Do not perform the migration directly on the main development branch.

Create a dedicated branch:

git checkout -b spfx-1-24-migration

Commit the current working state before changing dependencies:

git add .
git commit -m "Baseline before SPFx migration"

This makes it easier to compare the migrated application with the original implementation.

Back Up the Existing Package Configuration

The package.json file controls a large portion of the project's development environment.

Before editing it, preserve the existing version information.

A simplified dependency section might contain:

{
  "dependencies": {
    "@microsoft/sp-core-library": "...",
    "@microsoft/sp-webpart-base": "...",
    "@microsoft/sp-http": "...",
    "react": "...",
    "react-dom": "..."
  }
}

Do not randomly upgrade unrelated packages at the same time.

A controlled migration should make it clear which dependency caused a compatibility problem.

Upgrade SPFx Packages Consistently

SPFx packages should generally remain aligned with the target framework version.

For example:

@microsoft/sp-core-library
@microsoft/sp-webpart-base
@microsoft/sp-http
@microsoft/sp-property-pane

should not be upgraded independently to unrelated SPFx versions.

After updating the package definitions, reinstall dependencies:

rm -rf node_modules
npm install

On Windows PowerShell, the equivalent cleanup can be performed with the appropriate PowerShell command:

Remove-Item -Recurse -Force node_modules
npm install

The exact package-management workflow should follow the project's existing lock-file strategy.

React 18 Compatibility

React 18 changes the rendering model and introduces APIs that differ from older React versions.

A common older entry point looks like:

import * as ReactDOM from 'react-dom';

ReactDOM.render(
  <App />,
  element
);

React 18 introduced the root-based API:

import { createRoot } from 'react-dom/client';

const root = createRoot(element);

root.render(
  <App />
);

However, developers should not blindly replace every React rendering call in an SPFx solution.

SPFx manages important parts of the web part lifecycle, and the correct integration pattern depends on the SPFx component being migrated.

The goal is framework-compatible rendering, not simply converting every React API manually.

Review ReactDOM Usage

Search the project for:

ReactDOM.render
ReactDOM.unmountComponentAtNode
createRoot
hydrateRoot

You can search using your editor or command-line tools.

For example:

grep -R "ReactDOM.render" src

On Windows:

Get-ChildItem -Recurse src |
    Select-String "ReactDOM.render"

This helps identify components that rely on older rendering APIs.

Check Component Lifecycle Code

React 18 compatibility also means reviewing lifecycle-related assumptions.

For example:

componentDidMount() {
    this.loadData();
}

The code itself may still compile, but changes in rendering behavior can expose assumptions around:

• Side effects

• Repeated execution

• State updates

• Cleanup

• Async operations

For functional components, review useEffect carefully:

React.useEffect(() => {
    loadData();

    return () => {
        // Cleanup resources.
    };
}, []);

Cleanup becomes particularly important for event subscriptions, timers, and other resources that can survive longer than expected.

Review Third-Party React Libraries

This is one of the most important migration steps.

An SPFx solution may depend on libraries such as:

UI component libraries
Chart libraries
Date libraries
Form libraries
State-management packages
Rich-text editors

A package can be compatible with React 17 but fail with React 18.

Create a dependency review table:

Do not assume that because npm install succeeds, the package is compatible.

Check Peer Dependency Warnings

After installation:

npm install

review warnings carefully.

For example:

npm WARN ERESOLVE

can indicate incompatible peer dependencies.

Do not automatically solve these warnings with:

npm install --force

or:

npm install --legacy-peer-deps

These options can suppress dependency resolution problems without actually fixing compatibility.

First determine which packages are conflicting.

TypeScript Compatibility

SPFx projects are sensitive to the TypeScript version supported by the target SPFx release.

Do not independently upgrade TypeScript to the newest available version unless it is supported by the target framework version.

Check the project:

{
  "devDependencies": {
    "typescript": "..."
  }
}

Then compile:

npx tsc --noEmit

If the project uses SPFx's build pipeline, also run the standard build command.

Run the SPFx Build

After dependency migration:

gulp clean
gulp build

Then:

gulp bundle

And package the solution:

gulp package-solution

A successful build indicates that the source and dependency graph are compatible enough for compilation.

It does not prove runtime compatibility.

Test the Local Workbench

Start the local development environment:

gulp serve

Test every migrated web part.

Check:

Web Part Loading
Property Pane
Data Retrieval
User Interaction
State Updates
Event Handlers
Error Handling

Do not limit testing to the first screen that loads successfully.

Test in the SharePoint Environment

The local workbench cannot reproduce every Microsoft 365 behavior.

Validate the solution in the actual SharePoint environment used for testing.

Pay particular attention to:

• Authentication

• Microsoft Graph access

• SharePoint REST calls

• Permissions

• List and library access

• Web part configuration

• Responsive behavior

• Teams-hosted scenarios where applicable

A solution can behave correctly locally while failing because of permissions or environment-specific configuration.

Check SharePoint API Calls

Review existing API code:

const response =
    await this.context.spHttpClient.get(
        endpoint,
        SPHttpClient.configurations.v1,
        {
            headers: {
                Accept: 'application/json'
            }
        });

The migration itself should not require unnecessary API rewrites.

If API behavior needs to change, keep that change separate from the framework migration whenever possible.

This makes troubleshooting much easier.

Verify Property Pane Components

Property pane controls are another area that should be tested after migration.

Check:

Text fields
Dropdowns
Checkboxes
Toggle controls
People pickers
Custom property controls

For example:

PropertyPaneTextField(
    'title',
    {
        label: 'Title'
    }
)

Verify that property changes still propagate correctly into the React component.

Check State Management

Older applications may use:

Component State
Redux
Context API
Custom Stores
Observable Patterns

React 18 migration is a good opportunity to inspect state transitions.

For example:

const [loading, setLoading] =
    React.useState(false);

const [items, setItems] =
    React.useState<Item[]>([]);

When asynchronous operations are involved, ensure state updates are not performed after a component has been disposed or replaced.

Handle Async Operations Carefully

A common pattern is:

React.useEffect(() => {
    loadItems();
}, []);

A safer implementation should consider cancellation or cleanup when the underlying operation supports it.

For example:

React.useEffect(() => {
    const controller =
        new AbortController();

    loadItems(controller.signal);

    return () => {
        controller.abort();
    };
}, []);

The exact implementation depends on the API being called.

The important principle is to avoid unmanaged asynchronous work.

Check Strict Mode Behavior

Development configurations may expose side-effect problems that were previously hidden.

For example:

<React.StrictMode>
    <App />
</React.StrictMode>

Developers should understand the behavior of their development configuration rather than interpreting every repeated development-side effect as a production defect.

If initialization code assumes it can only execute once, make that assumption explicit and safe.

Compare Before and After Behavior

Create a migration checklist:

This gives the migration a clear acceptance criterion.

Test Third-Party Libraries Independently

If a web part uses a complex component:

<CustomChart
    data={data}
    onSelect={handleSelect}
/>

test:

1. Initial rendering

2. Empty data

3. Normal data

4. Large data sets

5. User interaction

6. Component updates

7. Component cleanup

This helps determine whether a problem comes from React, SPFx, or the third-party component.

Production-Like Validation

Before deployment, test scenarios such as:

Fresh Page Load
Page Refresh
Web Part Configuration Change
Multiple Web Parts on One Page
Navigation Between Pages
Permission Restrictions
API Failure
Slow Network
Missing Data
Expired Authentication

The goal is to validate the complete lifecycle rather than just successful rendering.

Common Migration Mistakes

Upgrading Everything at Once

Changing SPFx, React, TypeScript, UI libraries, and unrelated dependencies simultaneously makes failures difficult to isolate.

Ignoring Peer Dependency Warnings

A successful installation does not guarantee runtime compatibility.

Blindly Replacing ReactDOM APIs

React 18 introduced new rendering APIs, but SPFx manages its own lifecycle integration.

Using --force to Hide Problems

Forced dependency installation can leave incompatible packages in the project.

Testing Only the Local Workbench

Real SharePoint permissions and APIs may behave differently.

Forgetting Third-Party Components

A React-dependent package can be the actual source of a migration failure.

Treating Build Success as Migration Success

Compilation does not validate runtime behavior.

Troubleshooting

Build Fails After Package Upgrade

Check:

1. SPFx package versions.

2. Node.js compatibility.

3. TypeScript version.

4. Peer dependency warnings.

5. Lock-file changes.

6. Third-party package versions.

Then run:

gulp clean
npm install
gulp build

React Component Does Not Render

Inspect:

React version
ReactDOM usage
Component lifecycle
Third-party dependencies
Browser console errors

Property Pane Stops Updating the Component

Check whether the web part's property values are still passed correctly into the React component.

Third-Party Component Crashes

Check its peer dependencies and React compatibility before changing the SPFx implementation.

Local Testing Works but SharePoint Fails

Check:

• Permissions

• API endpoints

• Authentication

• Tenant configuration

• Package deployment

• Environment-specific settings

Multiple API Calls Appear Unexpectedly

Inspect component effects, initialization code, and development-mode behavior before assuming the framework is issuing duplicate requests.

Best Practices

1. Create a dedicated migration branch.

2. Record the existing dependency versions before starting.

3. Upgrade SPFx packages consistently.

4. Use the Node.js and TypeScript versions supported by the target SPFx release.

5. Review React and ReactDOM usage.

6. Audit third-party React dependencies.

7. Treat peer dependency warnings as real compatibility signals.

8. Avoid unrelated dependency upgrades during the migration.

9. Test both local and SharePoint-hosted environments.

10. Validate property pane behavior.

11. Test API calls and authentication.

12. Review asynchronous effects and cleanup.

13. Test multiple web parts on the same page.

14. Run a clean build before packaging.

15. Compare pre-migration and post-migration behavior.

16. Keep rollback options available until production validation is complete.

Advantages and Disadvantages

Advantages

• Provides access to a newer SPFx development baseline

• Enables compatibility with supported modern React patterns

• Provides an opportunity to remove obsolete dependencies

• Encourages cleaner component lifecycle handling

• Can simplify future framework maintenance

Disadvantages

• Migration can expose hidden dependency problems

• Third-party React libraries may require upgrades

• Build-tool compatibility must be verified

• Runtime issues may not appear during compilation

• Large SPFx solutions can require extensive regression testing

• Multiple simultaneous dependency changes make troubleshooting harder

Migration Checklist

Use this checklist before considering the migration complete:

[ ] Existing project committed
[ ] Migration branch created
[ ] Current dependency versions recorded
[ ] SPFx packages aligned
[ ] Supported Node.js version verified
[ ] Supported TypeScript version verified
[ ] React dependencies reviewed
[ ] ReactDOM usage reviewed
[ ] Third-party libraries audited
[ ] Peer dependency warnings resolved
[ ] gulp clean completed
[ ] gulp build completed
[ ] gulp bundle completed
[ ] Solution package generated
[ ] Local workbench tested
[ ] SharePoint environment tested
[ ] Property pane tested
[ ] API calls tested
[ ] Authentication tested
[ ] Multiple web parts tested
[ ] Regression testing completed

A Safe SPFx Migration Workflow

A controlled migration can follow this sequence:

Existing SPFx Solution
        |
        v
Create Migration Branch
        |
        v
Record Current Dependencies
        |
        v
Update SPFx Dependencies
        |
        v
Validate React 18 Compatibility
        |
        v
Audit Third-Party Packages
        |
        v
Install Dependencies
        |
        v
Clean Build
        |
        v
Local Testing
        |
        v
SharePoint Testing
        |
        v
Regression Testing
        |
        v
Package Solution
        |
        v
Deployment Validation

Each stage provides an opportunity to stop before a compatibility problem reaches the next environment.

Conclusion

Migrating an SPFx solution to a newer framework baseline with React 18 compatibility requires more than updating a few entries in package.json. The framework, React runtime, TypeScript compiler, build tooling, and third-party packages form an interconnected dependency chain.

The safest approach is to upgrade incrementally, verify supported dependency versions, audit React-based libraries, and test the complete web part lifecycle.

A successful migration should satisfy more than:

gulp build
    ↓
Success

It should demonstrate:

Build
  +
Runtime
  +
SharePoint Integration
  +
Third-Party Compatibility
  +
Regression Testing
  ↓
Safe Migration

By treating SPFx migration as a compatibility and regression-testing exercise rather than a simple package upgrade, developers can identify problems earlier and reduce the risk of introducing runtime failures into existing Microsoft 365 solutions.