In-house training
Upskill teams in model standards, workbook structure, formula quality, maintainability and practical Excel discipline.
Excel model review, repair and rebuild
Make inherited Excel models faster, safer and easier to trust.
ExcelCodex helps hedge funds and finance teams analyse fragile workbooks, modernise legacy VBA models, improve robustness and upskill internal teams.
- In-house training
- Financial modelling
- Model review and rebuild
- AI-assisted workbook analysis
Services
Practical help for hard-to-maintain Excel environments
Financial modelling
Build high-end financial models for companies using a fully dynamic template model that can be adapted to suit the structure and commercial reality of each business.
AI-assisted tooling
Develop internal tools that automate the analysis, reporting and repair work traditionally handled manually across batches of workbooks.
Legacy rebuilds
Rebuild older VBA-heavy models into simpler, more robust structures with clearer logic, better performance and less hidden complexity.
Model review
Review inherited or problematic models to identify structural risk, dead content, style bloat, defined name issues, links and formula weaknesses.
Excel troubleshooting
Work with enterprise end-user computing teams to troubleshoot Excel performance and helpdesk issues, often leading into repair, upgrade and workbook stabilisation without forcing teams into a disruptive replacement project.
For other Codex services, go to codex-systems.com.
Back to topTraining
Modern Excel training for teams that need stronger modelling capability
In-house training can be tailored for finance teams, modelling teams and end-user computing functions that want to improve workbook quality, consistency and maintainability across business-critical Excel files.
A particular area of expertise is Modern Excel and Dynamic Arrays, including practical use in financial modelling. James has also delivered webinars on advanced use of Dynamic Arrays in financial modelling.
Core areas
- Excel general best practices, including what good looks like, what weak practice looks like and what should be avoided.
- Dynamic Arrays training at both basic and advanced level, with practical modelling use cases.
- VBA coding best practices, including structure, maintainability, readability, controls and common pitfalls.
- Training sessions are typically broken into focused one-hour blocks.
- Training can be shaped around real workbook examples so teams see the difference between robust design and fragile design in practice.
Recent Client Work
Trusted on complex Excel estates where the cost of workbook weakness is high
Recent work has included supporting a USD70bn fund with troubleshooting of users' Excel models, rebuilds, migrations, error fixing, removal of bloat and redundancy, performance optimisation, in-house training and helpdesk support.
Other assignments have included working with a USD30bn macro-driven fixed-income fund on in-house training, troubleshooting and full model rebuilds with extensive VBA, supporting the modelling division of a top 10 accountancy practice building project finance models for energy work, and helping CFOs of startups and early-stage ventures model financials for fund raising.
Typical assignments
- Troubleshooting fragile user models and resolving Excel performance issues.
- Rebuilding VBA-heavy workbooks and migrating older model structures.
- Removing bloat, redundancy and structural weaknesses from business-critical files.
- Building project finance and corporate forecasting models.
- Training internal teams and supporting helpdesk or end-user computing functions.
Products
Specialist products for workbook analysis and advanced forecasting models
Excel Toolkit
Analyse, report and repair workbooks without needing to run Excel
- Analyse workbook structure, defined names, styles, links, embedded content and circular references.
- Flag errors, volatile functions and problematic formulas.
- Build corresponding JSON output for downstream processing.
- Create workbook reports that prioritise key issues and optimisation needs.
- Run against folders of files, with optional recursive analysis.
- Produce consolidated Excel and Word reports across a batch.
- Feed key findings into AI-generated summaries and issue overviews.
- Check XML structure, clear dead space, prune names and remove style bloat.
- Run full verification after fixes are applied to confirm that model integrity has not changed.
Forecasting Model
Fully dynamic template financial model for SMEs in Modern Excel
We have developed a fully dynamic template model for SMEs in Modern Excel, built around Dynamic Arrays and designed to support multiple group entities, multiple business units, multiple currencies and flexible time periods.
It incorporates dynamic historical and forecast periods and can be customised for business-specific sales and cost-of-sales inputs, while the rest of the model framework is prebuilt.
The template includes overheads, equity, debt, VAT and corporation tax, fixed asset and working capital schedules, resulting in a fully integrated set of financial statements on both a monthly and periodic basis.
It can also automatically import monthly output trial balances from major accounting systems, making it easier to connect historical reporting into the forecasting model without repetitive manual rework.
Media
Show me on YouTube
Featured webinar
Dynamic Arrays: Beyond the Basics
The introduction of dynamic arrays is one of the biggest changes to Excel in recent years, and particularly impacts financial modellers.
Watch to hear from financial modeller, James Buist, as he shows how to get the most from Dynamic Arrays with practical, time-saving techniques.
The session covers smarter flags and counters, repeating sequences, period rollups and corkscrew calculations, as well as simple multi-row or conditional accumulations that help build cleaner, faster models that save time and reduce errors.
Watch on YouTube
Companion Download
Request the sample model used with the webinar
Enter your email address and we will send you a download link for the sample workbook that goes with the Dynamic Arrays webinar.
LinkedIn posts
- June 5, 2023: Excel - A Curse or a Blessing?
- June 14, 2023: Excel - To Iterate or Not To Iterate?
About James
Deep Excel expertise backed by finance, modelling and operational experience
ExcelCodex is led by James Buist, a senior Excel and financial systems specialist with more than 35 years of experience across financial services, spreadsheet engineering and operational process improvement. His career has included work in both London and Hong Kong, giving him a practical understanding of how complex models are built, used, inherited and often left harder to maintain than they should be.
James works at the point where financial modelling, Excel architecture and real-world operational demands meet. He has helped clients review problematic workbooks, rebuild legacy models, streamline reporting, strengthen controls and train in-house teams to work to a higher standard. His recent work also includes the development of AI-assisted tooling to automate parts of workbook analysis, repair and optimisation.
He also has deep expertise in Modern Excel and Dynamic Arrays, both as a modelling technique and as a way to simplify workbook design. This includes building dynamic financial models and presenting webinar sessions on advanced use of Dynamic Arrays in financial modelling.
Advanced Financial Modeler (AFM)
Accredited by the Financial Modeling Institute, validating advanced financial modelling capability across finance, accounting, Excel and model design.
CFA Charterholder
CFA designation awarded in 1998, reflecting advanced investment knowledge, technical competence and adherence to professional standards.
Contact
Have a workbook problem, legacy model or training need?
Start with a conversation about the issue, the constraints and the shape of a sensible fix.