Thomas McCallum, Developer in Elgin, United Kingdom
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Thomas McCallum

Verified Expert  in Engineering

Data Analytics Developer

Elgin, United Kingdom
Toptal Member Since
August 28, 2020

Tom is a software engineer and data analyst with over 10 years of experience. He has worked directly for companies such as Capgemini UK Plc and for clients such as Aladdin Capital UK. An ability to adapt to new and legacy technologies allows Tom to take on roles with security constraints or limited handovers. He prefers projects that use both his knowledge in data analysis and software engineering.


University of Highlands and Islands
IBM z/Transaction Processing Facility (z/TPF), COBOL, IBM Cloud, Bash Script...
University of Highlands and Islands
IBM Cloud, Bash Script, Microsoft Excel, Linux, Data Analytics, Apache2, Agile...
Capgemini UK Plc
Bash Script, Microsoft Excel, Visual Basic for Applications (VBA), Linux...




Preferred Environment

Linux, Vi, Git, Visual Studio Code (VS Code)

The most amazing...

...project I've worked on was creating a risk management system for a Fund of Funds to analyze hedge fund performance—an interesting mix of dev and data analysis.

Work Experience


2020 - PRESENT
University of Highlands and Islands
  • Taught modern software development languages to students including JavaScript, C++, and Python.
  • Taught cloud practices to students based on IBM Cloud. Schooled students in how Kubernetes and Docker can be used to scale applications in the Cloud.
  • Taught Agile Project Management to students. Facilitated students in daily standups, setting goals, and reviewing progress as they progressed with project work.
Technologies: IBM z/Transaction Processing Facility (z/TPF), COBOL, IBM Cloud, Bash Script, Microsoft Excel, R, Linux, Data Analytics, Python 3, Java, C++

Academic Lead Developer

2018 - 2020
University of Highlands and Islands
  • Designed and implemented a student work tracking application that tracks submissions to a student's Git repository and gives them feedback on their progress.
  • Created learning materials for a range of modern software technologies and project management techniques including IBM Cloud, Docker, Kubernetes, IBM Watson, React Native, and Agile practices.
  • Created materials for teaching programming, database systems, and computer systems to teachers transitioning to computer science from other subjects.
  • Led the requirements capture phase, discussing with software companies throughout the UK including IBM, Sky, and Adobe to understand the needs and requirements for future software developers and engineers.
Technologies: IBM Cloud, Bash Script, Microsoft Excel, Linux, Data Analytics, Apache2, Agile, Python 3, C++, MySQL, PHP 7

Infrastructure Lead and Senior Engineer

2015 - 2018
Capgemini UK Plc
  • Maintained enterprise systems for public sector clients including RedHat Linux, Solaris, HP Tandem Nonstop and HP-UX. Worked with project teams to implement new features with minimal downtime.
  • Designed and implemented tools for automating service infrastructure in secure and non-secure public sector estates.
  • Led a team of 60 engineers for servicing large public sector server estates. Led the technical response to managing high priority level incidents liaising with account managers.
  • Managed automation effort to reduce daily service tickets from hundreds down to low ten's through increased process documentation, automation, and proactive estate management.
  • Mentored junior colleagues, developing their confidence and technical knowledge in scripting for managing Linux and HP-UX systems.
Technologies: Bash Script, Microsoft Excel, Visual Basic for Applications (VBA), Linux, Genetic Algorithms, IT Services, ITIL, HP-UX, Solaris

Developer and Data Analyst

2012 - 2014
  • Designed and implemented the front end for a data analytics platform using HTML, CSS, Bootstrap, and jQuery.
  • Implemented tools to interact with public APIs and websites to gather data on a regular basis and update a local PostgreSQL database.
  • Designed and implemented tools in R to run in response to user queries to analyze NHS, Land Registry, OpenStreetMap data, Office of National Statistics, and MoJ data to identify new opportunities for purchasing land to build new care homes.
  • Created tools using VBA and Office applications to automate the creation of standardized brochures for properties based on the data from the analytics platform.
  • Created financial modeling tools in Excel to help forecast the impact of business model changes to the debt over daily, weekly, and monthly timeframes.
  • Designed and implemented an application to allow staff with little technical skills to design forms to allow the company to capture important business information from distributed locations.
Technologies: Finance, Bash Script, Apache, Microsoft Excel, Visual Basic for Applications (VBA), R, Linux, Data Analytics, jQuery CDN, Bootstrap, jQuery, Apache2, MySQL, C++, PostgreSQL


2007 - 2012
Gulfstream Software Limited
  • Implemented risk management and CDS trading systems for Aladdin Capital UK.
  • Designed and implemented statistical techniques for analyzing the investment practices to match whether a hedge fund trading record matched its marketed trading strategy.
  • Led client-facing activity including requirements analysis for system design and presentations to client management teams.
  • Coordinated a small team of four junior and senior developers.
  • Developed R libraries to improve the performance of existing financial models.
Technologies: Finance, Bash Script, Apache, Microsoft Excel, R, Linux, Bootstrap, jQuery, MySQL, C++

Lead Developer and Team Builder

2005 - 2007
Level E Limited
  • Designed and implemented real-time trading systems in R and C++ based on client specifications.
  • Designed and implemented an experiment platform for testing trading strategies against defined metrics and feeding back results to analysts.
  • Interviewed and made hiring decisions to build a technical team from two to eight over the course of 12 month period.
  • Designed and implemented tools to translate rule-based systems from other trading software into R and C++ modules.
Technologies: Finance, Bash Script, Apache, Microsoft Excel, R, Linux, Data Analytics, C++, MySQL, Genetic Algorithms, Neural Networks, Java

Dashboard for Student Learning Outcome Tracking

The objective was to allow students to monitor their progress throughout a range of projects towards fulfilling a set of learning outcomes.

The application was comprised of a WordPress plugin written in PHP 7. This design decision was chosen as it enabled us to utilize existing capabilities of WordPress that were not central to the core requirement. It had a separate MySQL database to store data about the student's work.

A scheduled cron task was created to regularly download the student commits from the repositories and store this data in the database. To provide meaningful visualizations to the student an R background process analyzes the student progress and maps this against an expected trend.

The tool used a Docker instance to allow for a clean environment for unit testing.

The challenges were around picking a framework and technologies that could be continued by staff after development ended. It also had to fit in with existing technologies that the university used, which constrained the design.

This was developed as an internal project and therefore is not available to the public.

Genetic Algorithm for Load Balancing a Veritas High Availability Cluster

This was a piece of work that undertaken after a high availability cluster kept failing loads over causing high priority incidents. The objective was to provide a way to allow those in charge of managing the load on the cluster to match loads in such a way that they would not cause a failover. Due to the highly secure nature of the environment, the tool was created using Excel VBA to create a suitable simulator.

At the heart of the simulator was a genetic algorithm that optimized the workloads. It consisted of a set of shell scripts that took live data for the performance of each application on the cluster (memory, CPU, and IO). From this data, features were extracted that were used to optimize what loads could work together best.

This tool was developed for a secure environment and therefore source code is not available.

Tools to Automate Tasks on A High Secure Network with A Mix Of HP-UX, SuSE, and RedHat Linux

Due to the highly secure nature of public sector estates, it is hard to get new software on to them. This led to large amounts of manual effort being required to do relatively simple tasks that today would be taken care of by products like Ansible and Chef.

I developed a comprehensive set of bash scripts for automating a range of maintenance activities on a large highly secure estate without the need for additional application installations. The script was able to take another script written for a single application of the task and then run this across a set of machines in parallel highlighting errors when applicable. It handled all the login and security access requirements. These scripts were also later adapted to also run using PowerShell.

This solution led to tasks that did take days to minutes. It also allowed the team to provide security reporting that otherwise would have taken weeks to get the information for.

These tools were developed for a secure environment and therefore source code is not available.

Data Analytics platform for Property Investments using UK Public Sector Data Sources

The challenge was to produce a dashboard that would allow a large property company to identify new land purchases for care homes.

The solution I developed was a web dashboard written in PostgreSQL and PHP (back end) and JavaScript (front end). It used R to do the analytics in an offline process.

The application processed data from the Office for National Statistics, NHS, OpenStreetMap, Land Registry, and other public data sources. Due to the changing nature of the data from these sources, the tools were flexible in how they could analyze the structure of the data and export information in a way that was in a consistent format that could be analyzed.

As an additional requirement, it was possible to generate brochures for existing properties from this information through a pipeline developed in VBA. The reason for using VBA in this instance was that the brochure inputs and outputs needed to be modified by non-technical individuals who were able to use Powerpoint and Excel.

This was an internal project contracted under NDA.

Hedge Fund Analysis and Risk Management

The challenge was to create an analytics platform and dashboard that could take in data from HFN and Lippa and query performance details about individual or groups of hedge funds.

The solution was a web-based tool that allowed the user to mix and match financial instruments with hedge fund performance trends. Having taken in data from Bloomberg, HFN, and Lippa. It corrected the data and made it accessible for benchmarking and clustering. A range of mathematical analyses was run on the data to allow for investment decisions to be made.

The solution required a number of new modules to be created for R in C/C++ to help analyze the quantify of data.

Technologies included: R, PHP, MySQL, C++ (for creating native R libraries)

This was an internal project contracted under NDA.
2002 - 2005

PhD in Artificial Intelligence

University of Edinburgh - Edinburgh, Scotland

1998 - 2002

First Class Bachelor of Science Degree (Hons) in Computer Science and Artificial Intelligence

University of Edinburgh - Edinburgh, Scotland


Master the Mainframe Level 2



IBM Blockchain Essentials




APMG International


CISI Hedge Fund Management

Chartered Institude of Securities and Investments


jQuery, jQuery CDN


Git, Apache, Microsoft Excel, JCL


Linux, Solaris, HP-UX, Apache2


Bootstrap 3, Bootstrap


C++, R, Bash Script, Visual Basic for Applications (VBA), Python 3, PHP 7, Java, COBOL, REXX


MySQL, PostgreSQL


Agile, ITIL, Unit Testing


Data Analytics, IBM Cloud, Vi, Finance, IT Services, Genetic Algorithms, Neural Networks, IBM z/Transaction Processing Facility (z/TPF)

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