Libraries

Last updated: 2026-05-19

Libraries

The EPAS Client Library is available through three wrapper families with the same core integration model:

.NET for Windows and .NET Framework based ECR applications
Java for Java and Android-adjacent integrations
Swift for macOS and iPadOS integrations

Each library page describes language-specific setup, callback shape, and runtime conventions while preserving the same terminal concepts and transaction flows.

Choose a Language Guide

Library	Use it for
.NET Library	.NET Framework setup, `Westpay.Epas`, synchronous transaction calls, and `IClientApp`.
Java Library	Java package layout, `Pair<ApiResult, T>` response patterns, and `IClientApp`.
Swift Library	Swift Package Manager setup, `async` or `await`, `throws`, and `EpasClientDelegate`.

Shared vs Language-Specific Documentation

Use the shared EPAS pages for cross-wrapper concepts:

Overview
Connection and Login
Transactions
Client Callbacks
Receipts and Events

Use the language pages for wrapper-specific syntax, packaging, and platform behaviour.