In the era of microservices, event streaming, and cloud-native architectures, many developers are surprised to discover that mission-critical enterprise workflows still run on... SFTP .

From banking reconciliation files (ACH/SEPA/CNAB) and healthcare records (HL7/EDI) to ERP batch processing (SAP/Oracle), SFTP remains the de facto protocol for secure, asynchronous B2B data exchange.

However, a quick search for C# SFTP tutorials reveals an unfortunate reality: most guides still promote patterns from a decade ago. They use synchronous blocking I/O, tightly couple business logic to concrete client classes, rely on temporary disk files, and lack automatic reconnects or transient fault handling.

In this article, we will examine the most common anti-patterns of SFTP implementations in C# and demonstrate how to build a clean, resilient, and testable SFTP integration in .NET 8+ using the open-source library SftpWrapper.Sdk .

4 Costly SFTP Anti-Patterns in .NET

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