GraphQL vs REST for Financial Applications: A Frontend Perspective
The Problem with REST in Financial UIs
- Account balances (from the accounts service)
- Recent transactions with merchant details (from the transactions service)
- Pending approvals (from the compliance service)
- Real-time exchange rates (from the pricing service)
Where GraphQL Wins for Fintech
1. Single Request, Exact Data
query DashboardView {
account(id: $accountId) {
balance
currency
lastUpdated
}
transactions(first: 10, filter: { status: COMPLETED }) {
edges {
node {
amount
merchant { name, category }
timestamp
}
}
}
pendingApprovals {
count
}
}2. TypeScript + GraphQL Codegen = Type Safety
string where you expected a number could display the wrong balance.
With GraphQL Code Generator, your queries produce fully typed TypeScript hooks:
// Auto-generated from your .graphql files
const { data, loading } = useDashboardViewQuery({
variables: { accountId: "acc_123" },
});
// data.account.balance is typed as number
// data.transactions.edges[0].node.amount is typed as number
// No runtime surprises3. Real-Time Financial Data with Subscriptions
subscription PriceUpdates($symbols: [String!]!) {
priceUpdate(symbols: $symbols) {
symbol
price
change
timestamp
}
}When REST Still Wins
- Simple CRUD operations: If your API is straightforward, REST's simplicity wins
- File uploads: REST handles multipart uploads more naturally
- Caching at the edge: REST's URL-based caching with CDNs is simpler than GraphQL's cache management
- Team familiarity: If your backend team is REST-native, the migration cost is real
The Practical Migration Path
- Start with read-heavy screens: Dashboards and reporting views benefit most from GraphQL
- Keep mutations in REST: Payment processing and sensitive writes can stay as REST endpoints
- Use Apollo Client's
RestLink: Gradually migrate endpoints without rewriting everything - Add codegen from day one: The type safety payoff is immediate
