Excel as a Main Programming Language: A Horror Story
Description
This image is a screenshot of a tweet from user Andrew Lynch (@andrewglynch), following the popular 'bizarre coding interview' meme format. The text reads: 'The most bizarre coding interview I've ever done was at Facebook when as usual I asked a candidate to write in any language of their choice.. And they nonchalantly said "I'll write it in Excel", to which I almost let loose a chuckle until...'. The punchline is an image of an extremely long and complex Excel formula, featuring nested functions like IF, OR, SUMIFS, and XLOOKUP, and referencing multiple sheets such as 'levels', 'Daily usage', and 'Delivery data'. This meme humorously highlights the shocking complexity that can be achieved within a spreadsheet. For senior developers, it's a relatable nightmare, representing the ultimate 'wrong tool for the job' scenario. While technically impressive as a demonstration of Excel's Turing-complete capabilities, such a solution in a real-world scenario would be an unmaintainable monstrosity, symbolizing a form of technical debt from the moment of its creation
Comments
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The solution was accepted, but now the company's core logic is a single cell in a spreadsheet that the finance intern is terrified to touch
Told the candidate they could use any language - so they opened Excel, wrapped a 12-level LET/LAMBDA around nested SUMIFS, and I realized our “cloud-native, event-driven microservice” is basically the same spreadsheet with more YAML
The candidate passed the interview and is now maintaining a critical production system that processes $50M in daily transactions through a VBA macro that nobody else understands or wants to touch
When they said 'any language,' they clearly didn't anticipate someone treating Excel as a legitimate programming environment - yet here we have a candidate who's essentially written a distributed transaction processor using SUMIFS and nested IFs. The real plot twist? This formula probably handles more production traffic than half the microservices at most startups, and unlike your Kubernetes cluster, it actually fits on one screen. The interviewer's suppressed chuckle turned into existential dread when they realized this person might actually be solving real business problems while the rest of us are bikeshedding over which functional reactive framework to adopt
Excel is the only "language" where your DAG is a workbook and deployment is emailing v23-final-FINAL.xlsx - yet that XLOOKUP+SUMIFS join still beats half the services in our data mesh
Offer “any language” in an interview and you’ll discover the enterprise’s true runtime: a reactive, globally mutable, grid-based monolith where XLOOKUP is RPC and SUMIFS the reducer - aka Excel, the only production system with no package manager, no grep, and unlimited circular dependencies
Excel: the language where every PM's 'quick fix' becomes your architectural nightmare