Replace a spreadsheet that broke under load
Turn the 47-tab spreadsheet everyone's afraid to touch into something that won't melt next quarter.
Save your progress on this path — check off each section as you go.
Create a free accountWhat you'll have at the end
A real app with the same data, the same logic, and the same people using it — except now two people can edit it at once, history is automatic, and you don't need to remember which tab has the 'real' numbers.
01
Who this is for
- Teams whose 'source of truth' is a Google Sheet older than the company
- Anyone who has typed the words 'don't touch the pivot tab'
- Builders who already shipped one tiny app and are ready for something with real data
02
How to frame the idea
The spreadsheet is the spec. Don't redesign — replicate. Get the same columns, same filters, same sort order live first, then start adding the things the sheet couldn't do: real permissions, edit history, validation that doesn't depend on conditional formatting.
03
What people actually build
Client tracker → client CRM
The sheet has 12 clients and 30 columns. Move it to a real app with proper records, statuses, and a notes timeline.
Project board → milestone tracker
Replace the 'project status' tab everyone copies. Now Mondays don't start with 'who updated this?'
Asset registry → equipment app
Devices, warranties, who has what. The sheet broke at 200 rows; the app handles 5,000.
04
Tool choices, honestly
Lovable + Lovable Cloud
You want UI + database + auth in one go without standing up infrastructure.
Supabase direct
You're comfortable with SQL and want to design the schema before you describe the UI.
Retool / Glide
You'd rather point at the existing sheet and skin a UI on top while you decide whether to fully migrate.
05
Prompts you can lift
Schema-first
Prompt by PromptlyDo™Here are my spreadsheet columns: <paste headers + 3 sample rows>. Design a normalized database schema. Tell me which sheet columns become tables vs columns, where the foreign keys go, and what validation rules I should enforce. Don't write any UI yet.
Migrate the data
Prompt by PromptlyDo™Generate a CSV import script that takes my sheet (column mapping: <mapping>) and inserts into the tables you just designed. Skip empty rows. Log anything that doesn't validate so I can review.
Lock multi-user safety
Prompt by PromptlyDo™Two people might edit the same record at the same time. Add optimistic UI with a clear 'someone else updated this — refresh' message. Don't let one person silently overwrite the other.
Save and reuse these prompts in PromptlyDo™ with your favorite AI.
- Install the PromptlyDo™ browser extension
- Sign in or create a free account
- Right-click any prompt above and save it to PromptlyDo™
06
What tends to break
- Rebuilding the spreadsheet pixel-for-pixel including the broken bits. Take the chance to drop columns nobody filled in.
- Forgetting history. The sheet was bad but at least it had version history. New app should too.
- Bulk imports that silently swallow bad data. You'll find out three months later when a report is off.
- No backup of the original sheet before you cut over. Always keep the sheet read-only for 90 days.
07
What AI forgot to ask you
- Who's allowed to edit vs view? The sheet had no answer — the app needs one.
- What's the unique key for each row? Names are not unique. Emails change.
- What happens to the formulas that referenced this sheet from elsewhere?
- Which 'inferred' columns (the ones with a formula) are now derived in the app, and which are stored?
08
Before real users see it
- Data migrated, row counts match, spot-checks pass.
- Two people editing different records at the same time both succeed.
- Two people editing the same record see a conflict warning.
- I can export back to CSV in 10 seconds if I need to.
- The original sheet is locked read-only with a 'use the app' banner.
09
Questions to sit with
- 1.Which spreadsheet behaviors am I keeping, which am I dropping, and which am I improving?
- 2.Who owns this app once it's live — and do they have edit access to the schema?
- 3.If the app went down for 4 hours, what would the team do? If the answer is 'panic,' you need a fallback.
Beginner safety net
Before real users see it — the short list.
Tick what's true. The unticked ones are your remaining work.
Before you share it
Before Real Users Checklist
The minimum bar before you put something in front of real humans. Not all of these are technical — most aren't.
Ready to app it?
Take this path into your tool of choice — and when you finish (or get stuck), share what you learned so the next builder doesn't reinvent it.