Introduction
Integration requirements
SolFi is a server-to-server REST API. There is no SDK to install and no client library to embed: any language that can send an HTTPS request and parse JSON can integrate with it.
Calling the API
| Requirement | Detail |
|---|---|
| Protocol | HTTPS |
| Format | JSON request and response bodies — Content-Type: application/json |
| Authentication | x-api-key and x-api-secret headers on every request |
| Client | Any HTTP client — curl, Node.js, PHP, Python, Java, Go, .NET, … |
No specific framework, runtime version or operating system is required.
Server-side only
Never call the SolFi API from a browser, a mobile app, or any other client-side code. Your x-api-secret grants full access to your account and its balances. Anything running on a user's device can be inspected or decompiled, so a key shipped in a web page, a mobile binary or a desktop app must be considered compromised the moment it is released.
Route every call through your own backend: your app talks to your server, and your server talks to SolFi.
Receiving callbacks
To be notified of transaction outcomes, your system must expose an endpoint that is:
| Requirement | Detail |
|---|---|
| Publicly reachable | Accessible over HTTPS from the public internet — not behind a VPN or a private network |
A POST route | Accepting a JSON body |
| Fast | Returns an HTTP 2xx within 15 seconds |
Environments
SolFi provides two distinct environments for your integrations:
Development — testing and validation
Production — real transactions
Both environments use the same request format and the same endpoints. Only the base URL and the API key differ depending on the environment.