A normal week with the sheet
It has a name like MASTER_v7_FINAL. It has fourteen tabs, some hidden. Orders, pricing, stock, commission or scheduling all pass through it, and one person, usually the one who built it years ago, is the only one who knows which cells you must never touch.
When they are in, it works. When they are on holiday, people either wait or make careful changes and hope. When a number looks wrong, the question is always the same: 'Ask Dave, he knows how it works.'
You have probably tried to get someone else trained on it. It rarely sticks, because the knowledge is not in a manual. It is in a hundred small habits: paste values here, never sort that column, refresh the lookup before Friday.
How one file became the business
Nobody decided to run the company on a spreadsheet. It started as a quick way to track something, it worked, and each new need was bolted on as another tab or another lookup. Spreadsheets are very good at that, which is exactly why they end up carrying rules that should live in a proper system.
The root problem is that the sheet mixes three things that should be separate: the data itself, the business rules applied to it, and the steps a person follows to use it. When all three sit in one file and one head, you cannot hand any of them over.
There is also a quieter cause. The person who owns it is usually busy and good at their job, so nobody wants to take their time to write it all down. The risk grows because the sheet keeps working.
The price of a single point of failure
| What happens | What it costs you |
|---|---|
| The owner is off sick or leaves | Work stops or continues on guesswork |
| A formula is overwritten by accident | Wrong figures reach customers or payroll before anyone notices |
| Two people open it at once | Conflicting copies, and a morning spent merging them |
| Someone asks why a number is what it is | Nobody can trace it without the owner |
| The business grows | The file slows, breaks, and gets split into more files |
None of these show up on a profit and loss statement as a line item. They show up as late evenings, cautious staff and decisions made on numbers nobody fully trusts.
How SpiderHunts takes the sheet apart safely
We do not start by throwing the spreadsheet away. It is the best specification you have, because it encodes years of decisions. Our method is to read it properly before replacing anything.
- Sit with the owner and walk through a real week. We record which tabs they touch, in what order, and why.
- Trace every formula and lookup, and write each business rule in plain English: 'commission is paid at the standard rate unless the customer is on the legacy rate'. The owner confirms each one.
- Separate the data into a proper database (usually PostgreSQL) with defined fields, so a date is always a date and a customer exists once.
- Build a small web application with screens for each job the sheet does: enter an order, update stock, run the Friday numbers. Each screen only shows what that job needs.
- Put the rules in code with validation, so an impossible value is rejected at entry rather than discovered at month end.
- Add an audit trail, so every change records who made it and when.
- Run the new system alongside the sheet and compare outputs until the numbers match, then retire the sheet. An export to Excel or Google Sheets stays available for anyone who wants to slice the data.
If parts of the sheet are genuinely fine as a spreadsheet, such as a one-off analysis tab, we leave them alone. The aim is to move the fragile, shared, rule-heavy parts, not to ban spreadsheets.
Life after the master file
Anyone with the right permission can do the daily jobs, because the screens guide them. The owner stops being the help desk and gets their time back for the work they were hired to do.
When a number is questioned, you open the record and see its history. When the owner is on holiday, nothing waits. And the rules that used to live in their head are written down in the system and in plain language documentation, where the next person can read them.
Does this sound like your office?
- One named person is the only one allowed to edit a key spreadsheet.
- People say 'do not touch that column' as a matter of routine.
- There are several versions of the file and you are not sure which is current.
- A holiday or sick day means certain work simply waits.
- You have found an error in the sheet that had been wrong for a while.