Rapid Addition FIX API refers to the FIX (Financial Information eXchange) protocol solutions provided by Rapid Addition, a financial technology company specializing in low-latency trading and market connectivity platforms.
Fragmentation, regulation, and market volatility continue to create an ever-more complex trading environment with Exchanges, MTF’s, and other execution venues all vying to differentiate themselves and attract flow. Technology is key to seeking liquidity with smart order routing and low-latency, at an affordable price, becoming ever-more essential in the quest to show a realisable return on investments.
Rapid Addition has seen a number of common key challenges with our clients such as;
• Latency
• Complexity of integration with clients
• Managing market data bandwidth
Rapid Addition are at the forefront of providing clients with a range of FIX and FAST engine solutions and products that enable them to gain that competitive edge, below are a range of our products that are used by a number of Exchanges globally.
What is Rapid Addition FIX API?
The Rapid Addition FIX API is a high-performance FIX engine interface that allows trading systems to:
• Send and receive FIX messages
• Connect to brokers, exchanges, and liquidity providers
• Handle real-time trading workflows (orders, executions, market data)
It is typically used as part of the Rapid Addition messaging infrastructure (RA Platform / FIX Engine).
Why do we use it?
We use Rapid Addition FIX API when building institutional-grade trading systems that require:
• Ultra-low latency communication
• High throughput order processing
• Robust FIX session management
• Multi-venue connectivity (many exchanges/brokers)
Instead of building FIX logic from scratch, it provides a ready-to-use, optimized engine.
When should we use it?
Use Rapid Addition FIX API when:
• High-performance trading is required
• Algorithmic trading
• High-frequency trading (HFT)
• Multiple market connections are needed
• Connecting to multiple exchanges/brokers simultaneously
• Enterprise-level reliability is required
• 24/7 trading systems
• Fault tolerance and failover support
• Complex FIX workflows exist
• Pre-trade risk checks
• Smart order routing
• Multi-asset trading
Do NOT use it when:
• You are building a simple trading app or learning FIX
• REST/WebSocket APIs are sufficient
• Budget or infrastructure is limited
Key Features
High Performance
• Low-latency FIX message processing
• Optimized C++/Java-based engine (depending on deployment)
FIX Protocol Support
• FIX 4.0 → FIX 5.0 SP2 support
• Custom extensions for proprietary fields
Connectivity
• Multi-venue connectivity (brokers, exchanges, ECNs)
• FIX gateways and routing
Reliability & Recovery
• Session recovery (sequence number handling)
• Automatic resend request handling
• Failover and redundancy support
Market Data Handling
• Real-time streaming market data support
• Order book updates
Customization
• Plug-in architecture for business logic
• Custom risk and routing rules
Key Components
Typical Rapid Addition FIX stack includes:
1. FIX Engine
Core component that:
• Parses FIX messages
• Manages sessions
• Handles network communication
2. Gateway Layer
• Connects internal systems to external venues
• Translates and routes FIX messages
3. Session Manager
• Logon/logout handling
• Heartbeats and connection monitoring
• Sequence number tracking
4. Application Layer
• Trading logic (orders, strategies)
• Risk checks
• Execution handling
5. Message Router
• Routes messages between systems
• Supports multi-venue order distribution
Advantages
• Extremely low latency: Designed for high-frequency trading environments
• Highly scalable: Can handle thousands/millions of messages per second
• Enterprise reliability: Used by major financial institutions
• Multi-asset support: Equities, FX, derivatives, etc.
• Strong connectivity options: Easy integration with global trading venues
Disadvantages
• Expensive: Enterprise licensing and infrastructure costs are high
• Complex setup: Requires experienced engineers and infrastructure teams
• Overkill for simple use cases: Not suitable for small trading apps or learning projects
• Vendor dependency: You rely on Rapid Addition ecosystem
• Steep learning curve: Requires understanding FIX + platform architecture
RA Cheetah FIX – C# FIX Engine | Java FIX Engine | .Net FIX Engine
The RA–Cheetah™ FIX engine is the highest performing messaging engine for the FIX protocol. Whether you need a low-latency .NET / C# FIX engine or a low-latency Java FIX Engine, RA-Cheetah provides the lowest-latency FIX Engine available on the market today.
The RA–Cub FIX engine is an entry level FIX engine designed to give new entrants an affordable flexibility. RA-Cub provides a smooth upgrade to the RA-Cheetah FIX Engine so transition to a low-latency engine later on, should it be required, is a simple operation, requiring no new Systems Integration effort.
RA-Cub is available both as a .NET/C# FIX Engine and as a Java FIX Engine, with both versions being deployable to multiple environments.
How RA-Cheetah FIX engine enhances your trading capability:
Throughput:
• Increases messaging throughput; a single instance of RA-Cheetah FIX engine can process significantly more messages than any competitor
• Fullly scalable to meet your needs
Latency:
• Consistent low-latency message delivery with no nasty outliers
• Ultra low-latency with consistent measurement
• Continually optimised to further enhance performance, typically we are 35x faster than other FIX engines
• The only FIX vendor to conduct a continual program of testing in Intel's Low-Latency Labs
Cost:
• Higher performance from commoditised hardware
• Lower systems and operational costs
• Higher transaction volume processing = lower data centre footprint
• Reduced energy consumption: greener footprint
• Reduced Total Cost of Ownership (TCO)
• Accelerated return on investment (ROI)
Operational Flexibility of the Rapid Addition FIX API
• Simplicity
• Full in-flight session independence
• Full transport independence
• FIX repository-driven
• All versions of FIX-out-of-the-box from 4.0 to 5.0 (all service packs)
• Ease of integration & customisation (integration in days, not months)
• Supports local dialects and customised repositories
• Platform independent - available as a .NET/C# FIX Engine and as a Java FIX Engine
• Fully compatible with all FAST engines
• Support for direct integration with .NET and Java applications
• All versions can be run on Windows, Linux, UNIX, and Apple Mac
• C# version is "out-of-the-box" deployable as a stand-alone Windows service
Features of Rapid Addition FIX Engine
• Multiple logging options including; log to database, file, bespoke storage devices, and, of course, no logging
• Supports multiple session with different service windows
• Supports non-standard dialects and customisations
• Utilises FPL’s repository updates so new FIX releases are supported immediately
• Customisations applied quickly through configuration; no code updates
• Sample open source messages included as standard
• Supports TCP or UDP
• Supports multiple transports, including FIXT1.1
• Support for FIXML
• Available as a .NET/C# FIX engine or a Java FIX Engine
• Ability to support EMX
