Sorrell Consulting

Experience

Experience and technical work.

Sorrell Consulting is a founder-led engineering firm with commercial contracting experience. The practice connects architecture with hands-on delivery across modernization, distributed systems, and computational software.

Commercial engineering

Sorrell Consulting engagements

Representative projects and results from broader commercial engagements.

Sorrell Consulting engagement

Modernizing a fund‑accounting engine

Result

Production batch processing fell from 90 minutes to 10 minutes.

Problem

A core fund-accounting engine processed hundreds of gigabytes of financial data in a batch workload. Its object-oriented computation model took about 90 minutes to complete the processing run.

Role

Sorrell Consulting was engaged to redesign the engine. Joshua Sorrell designed the vectorized linear algebra approach and guided the client’s engineering team through implementation and delivery.

On Sorrell Consulting’s engagement at Citadel

I worked closely with Joshua at Citadel, where I was COO of Post-Trade Engineering. Joshua is one of the most impressive engineers I’ve worked with - not only technically brilliant, but someone who understood the business as well as, and often better than, the people on the business side.

A great example was our fund accounting calculation engine, an immensely complex and business-critical platform responsible for calculating returns across the hedge fund and its investors. It was a system that other developers struggled to fully understand, yet Joshua had an exceptional command of both the underlying technology and the business logic.

Despite its complexity and importance, he could diagnose and fix issues, build new functionality, and significantly optimize the platform without compromising its reliability. That combination of deep technical expertise, business understanding, and ability to work safely within highly complex systems made Joshua a huge asset to our organization.

Ravi SehraFormer Chief Operating Officer of Post-Trade Engineering · CitadelJoshua’s direct supervisor during the Citadel engagement.

Sorrell Consulting engagement

Moving batch processing to event-driven services

Result

Replaced an approximately four-hour end-of-day batch bottleneck with event-driven, incremental processing. Relevant source and state changes were processed as they occurred, so required downstream data was already available when scheduled end-of-day workflows began.

Problem

A financial-data workload ran as an approximately four-hour end-of-day batch. Dependent operational work and subsequent analytics waited behind it, compressing the overnight window before next-day client delivery.

Role

Sorrell Consulting was engaged to modernize the batch-processing workload. Joshua Sorrell designed the service architecture and led the migration to containerized services in Go. The work included recovery, backpressure, and observability.

Validation covered several years of historical data in user acceptance testing, followed by one month running the new system in parallel with production. Daily comparisons against the nightly batch results showed no differences before cutover.

Read the full batch-to-incremental case study

Founder background

Joshua Sorrell

Founder and Principal Engineer

Joshua Sorrell

Joshua is a U.S. Air Force veteran (2001–2007) who began his career as a Chinese linguist and intelligence analyst. He later supervised an operations section, with responsibility for personnel, training, scheduling, and operational performance.

As a research scientist at Georgia Tech Research Institute (2009–2011), he developed numerical algorithms for radar modeling and parallelized computational workloads. He also translated Chinese-language scientific and engineering research.

While employed as a principal data scientist at SAIC in Huntsville (2011–2016), he supported Army Materiel Command through the Software Engineering Directorate on Redstone Arsenal. His work turned logistics, resource allocation, forecasting, and operational planning problems into analytical projects and interactive decision-support software.

His financial-services work (2016–present) includes building and operating distributed compute and data platforms through both employment and Sorrell Consulting engagements. That work combines architectural direction with hands-on implementation on Kubernetes and AWS, alongside data engineering on Databricks.

Why Sorrell Consulting

Joshua’s earlier defense work grounded engineering decisions in mission needs and operating constraints. Financial-services work deepened his experience with distributed computation, data platforms, and production modernization. Sorrell Consulting brings those perspectives together for government programs and commercial organizations.

The focus is on changes that fit the mission, the existing system, and the people responsible for operating it. Architecture and implementation belong in the same conversation, with decisions shaped by operational and organizational constraints.

Writing & open source

Founder's public technical work

Explore Joshua’s technical portfolio

Let’s talk

Discuss relevant experience.

A project conversation can focus on the parts of this background that matter for your system, operating environment, and proposed scope.

Contact Sorrell Consulting