Main features

  • Easy-to-use
  • GC-Free (zero garbage is created while sending or receiving messages)
  • Ultra low latency performance for Direct Market Access (DMA), High Frequency Trading (HFT) and Algorithmic Trading applications
  • Comprehensive documentation
  • Quick start reference implementation source code for specific contexts
  • FIX Engine is supplied as a .NET class library (assembly) that offers complete flexibility over the implementation
  • FAST 1.1 and FAST 1.2 encoding and decoding
  • Session Scheduler
  • SSL encryption
  • FIX <-> FIXML converter
  • Supports multiple FIX Protocol versions simultaneously
  • Supports multiple FIX sessions simultaneously
  • Support all current FIX Protocol versions (4.0, 4.1, 4.2, 4.3, 4.4, 5.0, 5.0 SP1, 5.0 SP2, FIXML)

  • Supports all tag and message types of each FIX Protocol version (equities, fixed income, derivatives, FX etc)

  • Flexible support for user-defined tags and user-defined message types

  • Supports FIX Dialects (venue-specific interpretations of the FIX Protocol) on a per-session bases

  • Configurable validation of required fields

  • Persistence (the ability to log data to a flat file and restore the state after fail-over)

  • High-availability

  • Versatile diagnostics


Free 30 day evaluation

Request a demo

For a hands-on introduction

Further information

OnixS provides high-performance, low latency, scalable FIX SDKs based on the current and next generation .NET Standard platform technologies. OnixS has supported the .NET Standard based FIX Engine SDKs for over 12 years with a key value of using the OnixS SDKs being the forward migration based on technology platform, protocol and venue API changes.

The Microsoft roadmap for .NET Core/.NET 5 is new APIs and language features that the .NET Framework will not be updated to support. This means that the .NET Framework is still supported by Microsoft, and that .NET Core/.NET 5 is the future direction being an open source, cross-platform, and fast-moving onward developed version of .NET.

  • Cross-platform. Runs on Windows, Linux and macOS
  • Improved performance
  • Side-by-side versioning
  • Numerous new APIs
  • Open source community supported

Both .NET Core/.NET 5 and .NET Framework are current technology platforms and OnixS supports both, as well as the future direction of the .NET Core/.NET 5 platform.

Support and Reference

Online Reference

The OnixS .NET Framework and .NET Core/.NET 5 FIX Engine SDKs include the programming guide documentation, and quick start open-source reference implementation samples for:

  • Exchange Emulator
  • Trading Client
  • Sell Side
  • Buy Side
  • Repeating Groups handling
  • Session Scheduler
  • Latency benchmark
  • Throughput benchmark
  • FIX/FAST decoding benchmark
Supported platforms
  • .NET Framework 4.8
  • .NET Framework 4.7.2
  • .NET Framework 4.6.2
Linux, Windows and macOS
  • .NET Core/.NET 5