Introduction & Client Context

The client is a prominent financial services and wealth management firm operating in the highly regulated US market. Their business relies on empowering financial advisors with sophisticated tools to manage portfolios for high-net-worth clients. These operations involve high-volume trading of equities and options, requiring absolute precision to comply with strict industry regulations such as FINRA rules.

The client faced the dual pressure of maintaining legacy operations while modernizing their infrastructure to support a new Advisory Platform. They required a technology partner capable of navigating the complexities of US financial markets and delivering a stable, production-ready system. TIAC stepped in as a strategic engineering partner, tasked with building a resilient backend system to power their advisor workstations.

The Challenge

The primary challenge was operational fragmentation and data integrity. The client’s existing environment relied on disparate databases (PostgreSQL and SQL Server) with inconsistent account identifiers, creating significant risks for data reliability.

From a business perspective, the system needed to support complex trading scenarios with zero margin for error. Specific challenges included:

• Complex Order Lifecycles: The system had to manage intricate trade states, including partial fills, cancel/replace workflows, and market-close expirations.
• Interoperability: The solution required deep integration with a third-party Order Management System (OMS) for execution and a Back-Office system for booking. This necessitated precise protocol translation between JSON and FIX (Financial Information eXchange).
• Regulatory Compliance: The platform needed to enforce "Trade Rules" (such as checking account permissions for options or equities) before orders reached the market.
• Data Unification: The client required "Drop Copy" functionality to capture orders executed directly on the exchange or via other tools, ensuring their internal system remained the single source of truth.

The Team

TIAC assembled a dedicated cross-functional team of senior backend engineers and domain specialists. This team acted as technical consultants, helping to analyze the client's fragmented requirements and defining the logic for critical components like the Commission Engine and Trade Booking modules.

By mastering the domain—specifically the nuances of FIX protocol tags and financial workflows—the TIAC team successfully bridged the gap between the client's business goals and the technical realities of integrating modern cloud architecture with legacy financial systems.

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The Solution

TIAC engineered a modular, event-driven architecture hosted on Azure. The solution was designed to be resilient and scalable, processing high-frequency updates via asynchronous messaging.

Architecture and Data Flow The system is structured into three distinct API layers to ensure separation of concerns:

• Experience API: Handles requests from the user interface.
• Business API: Contains the core logic, including a custom Commission Engine to calculate fees in real-time.
• Interface API: Manages all external communications to ensure security and stability.

Core Workflows

• Order Execution: When an order is placed, it is published to a Kafka topic. A specialized "FIX Engine" consumes these messages, translates them into the FIX protocol, and routes them to the external OMS for execution.
• Real-Time Updates: As trades are executed or partially filled, execution reports are streamed back, converted to JSON, and processed by Azure Functions (Order Execution Processor) to update the system state immediately.
• Trade Booking: Once a trade is finalized, the system triggers a "Trade Booking" process. This splits the data into "Street Side" (exchange view) and "Client Side" (customer view) records, sending them to the back-office system for final accounting.

Handling Complexity To ensure data consistency, the team implemented time-triggered Azure Functions that run at market close. These functions automatically process expired orders and reconcile day-trades, ensuring the internal database matches the exchange state.

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The Results

The partnership delivered a stable, enterprise-grade backend that abstracted the immense complexity of financial trading for the advisors.

Key Outcomes:

• Operational Reliability: The system successfully automated the handling of complex "edge cases," such as multi-leg orders and partial fills, significantly reducing the risk of manual errors in trade booking.
• Unified Data Integrity: The successful implementation of "Drop Copy" processing allowed the system to ingest trades executed outside the platform, maintaining a unified and accurate view of all client positions.
• Client Satisfaction: The client's internal teams recognized the TIAC squad as "the best team they have worked with," citing the quality of the delivered code and the team's ability to navigate legacy infrastructure challenges.
• Regulatory Alignment: By implementing strict validations and real-time quote retrieval, the platform ensured advisors traded on accurate market data, reducing compliance risks.

Tech Stack

Back-end & Compute

• .NET / C#
• Azure Functions (Serverless compute)

Database & Storage

• PostgreSQL (Primary transactional database)
• SQL Server (Legacy data integration)

Messaging & Integration

• Apache Kafka (Event streaming)
• FIX Protocol (Financial Information eXchange)
• JSON (Internal data interchange)

Third-Party Integrations

• Order Management Systems (OMS)
• Back-office Clearing & Booking Systems
• Market Data Providers (Real-time quotes)

Lessons Learned & Future Direction

This project reinforced that in fintech, technical excellence is inseparable from domain expertise. The team’s ability to understand "Street Side" versus "Client Side" accounting was just as critical as their ability to write efficient C# code.

The architecture is designed to be extensible, laying the groundwork for future integrations with new open banking platforms and supporting the client's roadmap toward a direct-to-client trading portal.

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Real people. Real expertise. Real results.

Building mission-critical financial software demands a partner who understands the intricacies of your industry. At TIAC, we combine engineering maturity with deep domain knowledge to deliver systems that scale, perform, and comply.

Ready to build a solution that drives your business forward? Let’s talk.

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