John Gibbons, Software Architecture Developer in London, United Kingdom
John Gibbons

Software Architecture Developer in London, United Kingdom

Member since September 23, 2017
Since 1997, John has been working as a professional software developer. He started his technical career as an Excel RAD developer at Goldman Sachs and now specializes in system architecture and development on the Microsoft stack (Azure, ASP.NET Core/5, C#, Microsoft SQL Server). He communicates well, listens carefully to your requirements, comprehends what needs to get done, and then delivers high-quality well-tested code to move you forward.
John is now available for hire




London, United Kingdom



Preferred Environment

ASP.NET Core, C#, Azure, Azure Cosmos DB, Microsoft SQL Server, Blazor

The most amazing...

...system I've ever worked on was a globally distributed exotics risk management computing farm.


  • Software Architect and Lead Developer

    2019 - 2021
    Fortune 500 Oil Major (via Toptal)
    • Designed and implemented a complex back-end API used by multiple clients (iOS, Android, Blazor). Prototyping and coding were done using C# and Swagger OpenAPI. Authentication handled using Azure Active Directory and persistence using Cosmos DB.
    • Migrated the entire system to a new Azure tenant as part of the client's Azure rationalization program. Designed and implemented a large-scale bespoke data migration between Cosmos DB instances. Reconfigured Azure Active Directory authentication.
    • Designed data architecture to enable an infrequently connected iOS front-end app designed for field workers in remote locations to synchronize data efficiently and to be able to post back updated data efficiently when connected. Implemented in C#.
    • Designed a complex object model to capture sophisticated data entry requirements for field workers, including photo capture, signature capture, location-based GPS information, and complex nested form data.
    • Built and implemented Azure DevOps pipelines, including Azure ARM Templates to define Azure infrastructure and resources.
    Technologies: ASP.NET Core, ASP.NET MVC, Azure, Azure Active Directory, Azure Cosmos DB, API Design, RESTful Development, RESTful APIs, Entity Framework Core, Data Architecture, Blazor, C#
  • Senior Server Developer

    2017 - 2018
    Archer Daniel Midlands Investor Services International
    • Deployed a fully functional T+1 position report which was delivered via SFTP to brokerage clients. Used C#, .NET Core, and MS SQL Server.
    • Used ASP.NET Core 2.0 greenfield website and web API for client contact details management. The front end was built with Razor pages, Bootstrap 4 and JavaScript. It was hosted internally on IIS using integrated security.
    • Configured an entire DevOps pipeline for continuous integration and automated deployment. Used TeamCity and Octopus Deploy.
    • Redesigned a market abuse reporting (MAR) system to achieve MiFID II compliance. Used MS SQL Server, C#, .NET Core, and SSIS. The redesigned system handled three times the order volume completed, processed in ten percent of the time.
    • Accomplished all of the above in the context of typical tight deadlines, high-quality requirements, and stringent auditable requirements of financial regulatory projects.
    Technologies: ASP.NET Core, C#, .NET, Microsoft SQL Server, Blazor, Octopus Deploy, TeamCity
  • Senior Developer

    2017 - 2017
    MUFG Securities
    • Extended an existing C#/.NET quantitative analytics library with MIFID II compliant quote-recording functionality.
    • Integrated additional trading workflow features into an existing Excel add-in quant library; used Excel/Excel VBA, and C#.NET.
    • Designed and implemented greenfield back-end storage solution; used MongoDB and the operating system was RHEL Linux as the back-end storage solution. The cluster was a globally sharded cluster with hubs in Hong Kong, New York, and London. Wrote all Linux/Bash scripts for setting up and tearing down the clusters/nodes to achieve a high degree of automated deployment.
    • Contributed to a MongoDB C# driver open source community, including raising JIRAs to log issues and raising pull requests to solve them.
    Technologies: APIs, Excel Add-ins, Excel VBA, Microsoft Excel, MongoDB, .NET, C#
  • Senior Server Developer | DevOps Champion

    2015 - 2017
    Barclays Capital
    • Wrote a greenfield large scale queuing, reporting, and extracting framework for BCBS 239 regulatory reporting; used C# and MS SQL Server. The system watched for risk outputs from the in-house installation of interest rate risk management system and transferred via SFTP to Hadoop cluster.
    • Was nominated DevOps champion after building out a fully functional multi-platform DevOps pipeline capable of testing and deploying C# executive services, MS SQL Server databases, IIS-Hosted Web API services and AutoSys batch jobs.
    • Built an automated regression capability to analyze model change impacts, accelerate complex deliveries, and avoid regressions.
    • Led a team transition to behavior-driven development using specification by example (SpecFlow/NUnit) and presented at multiple internal conferences on BDD.
    • Worked as Agile Scrum Master to facilitate team deliveries, managed full set of Agile ceremonies including pre-planning/planning/demo preparation/retrospectives.
    • Coded multiple enhancements, extensions, and new components in the client's core C#, .NET, and MS SQL Server code base; also made heavy use of SpecFlow and NUnit.
    • Built a monitoring tool for the core MS SQL Server based back-end; used Excel and Excel VBA.
    • Advocated for an extremely friendly querying and debugging method of production issues and faster feedback during development.
    Technologies: TeamCity, Bash, NUnit, SpecFlow, Excel VBA, Microsoft Excel, RESTful Development, RESTful APIs, Microsoft SQL Server, C#
  • Global Platform Owner Prime Finance and Exotics

    2009 - 2015
    Credit Suisse
    • Delivered P&L attribution enabling traders to sign-off and on (and automatically flash) attributed P&L at EOD (C#, SQL Server, and Quant Analytics).
    • Coded an entitlements discovery Interface into a core SQL server database.
    • Managed and participated directly in the coding of a global upgrade from Windows XP to Windows 7—handlng 250 users across the major global financial centers (C#, SQL Server, and Quant Analytics).
    • Devised and coded an upgrade to core volatility surface model parameterization (Excel, Excel VBA, and Quant Analytics).
    • Rearchitected, designed, and implemented a new mechanism for storing and retrieving configuration and market data overrides into a trading book (SQL Server, C#, and Excel DNA).
    Technologies: Analytics, Excel VBA, Microsoft Excel, Microsoft SQL Server, .NET, C#



  • Languages

    Excel VBA, C#, Bash Script, JavaScript, Bash, ASP.NET Razor, HTML
  • Frameworks

    ASP.NET Core, ASP.NET MVC, SpecFlow, Windows PowerShell, NUnit, .NET, Entity Framework Core, Blazor, Razor Pages, Bootstrap, OAuth 2
  • Tools

    Excel 2010, Excel 2013, Excel 2016, Excel-DNA, TeamCity, Microsoft Excel, xUnit
  • Paradigms

    Behavior-driven Development (BDD), RESTful Development, REST, Agile
  • Platforms

    Azure, Firebase
  • Storage

    Microsoft SQL Server, Azure Active Directory, MongoDB, Azure Cosmos DB
  • Other

    Software Architecture, Financial Market Data, Embedded Software, Data Architecture, Web Applications, Web App Development, Fixed Income, Derivatives, Mathematics, RESTful APIs, Stock Exchange, Swaps, Options Trading, Octopus Deploy, Excel Add-ins, APIs, Analytics, API Design, Machine Learning
  • Libraries/APIs



  • Master of Arts Degree with Honors in Modern Languages and Philosophy
    1990 - 1994
    Oxford University - Oxford, UK


  • Machine Learning
    APRIL 2021 - PRESENT
    Stanford University
  • Microsoft Certified Professional
    MARCH 2015 - PRESENT
  • Microsoft Specialist: Programming in C#
    MARCH 2015 - PRESENT
  • Energy Risk Professional (ERP)
    APRIL 2014 - PRESENT
    Global Association of Risk Professionals (GARP)
  • Chartered Financial Analyst (CFA)
    CFA Institute

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