Every government, bank, airline, and hospital depends on the same 60 year old coding language.
It's used to move $3 trillion every single day.
The problem? Almost nobody alive knows how to write it.
Here’s what it is and why replacing it might be impossible: 🧵
It's used to move $3 trillion every single day.
The problem? Almost nobody alive knows how to write it.
Here’s what it is and why replacing it might be impossible: 🧵
1959: Grace Hopper, a Navy rear admiral and computer scientist, had a radical idea.
She believed programming shouldn’t be limited to mathematicians.
Instead, it should read like English so businesses could use it.
Her vision gave rise to COBOL.
She believed programming shouldn’t be limited to mathematicians.
Instead, it should read like English so businesses could use it.
Her vision gave rise to COBOL.
COBOL was built for one thing: money.
Payrolls. Ledgers. Transactions.
It became the perfect language for business.
By the 1970s, every major bank, insurer, and airline was running on it.
Payrolls. Ledgers. Transactions.
It became the perfect language for business.
By the 1970s, every major bank, insurer, and airline was running on it.
COBOL didn’t just process paychecks.
It powered ATMs.
Filed taxes.
Booked flights.
Handled insurance claims.
If money moved, COBOL was behind it.
It powered ATMs.
Filed taxes.
Booked flights.
Handled insurance claims.
If money moved, COBOL was behind it.
So how does COBOL work?
COBOL is like a giant calculator that speaks plain English.
Instead of weird math symbols, you can literally write:
“ADD salary TO total.”
The computer does exactly that.
COBOL is like a giant calculator that speaks plain English.
Instead of weird math symbols, you can literally write:
“ADD salary TO total.”
The computer does exactly that.
That simplicity made it perfect for banks.
They didn’t need rocket scientists to code.
They needed reliable instructions like:
“SUBTRACT payment FROM account.”
COBOL was money’s first native language.
They didn’t need rocket scientists to code.
They needed reliable instructions like:
“SUBTRACT payment FROM account.”
COBOL was money’s first native language.
Today?
95% of ATM transactions run on COBOL
80% of in-person bank transactions depend on it
Trillions of dollars move through COBOL code every single day
The global economy still runs on Hopper’s invention.
But there's a problem.
95% of ATM transactions run on COBOL
80% of in-person bank transactions depend on it
Trillions of dollars move through COBOL code every single day
The global economy still runs on Hopper’s invention.
But there's a problem.
The people who wrote this code are retiring.
Most COBOL programmers are in their 60s and 70s.
And almost nobody is learning it anymore.
Most COBOL programmers are in their 60s and 70s.
And almost nobody is learning it anymore.
The fragility became obvious in 2020.
U.S. unemployment systems (built on COBOL) crashed under pandemic demand.
Governors literally begged retired COBOL engineers to return and fix the code.
U.S. unemployment systems (built on COBOL) crashed under pandemic demand.
Governors literally begged retired COBOL engineers to return and fix the code.
The same fragility exists worldwide:
ATMs, healthcare, social security… still depend on COBOL.
A language invented in 1959.
And 95% of experts who know it will retire by 2030.
The irony? The real Y2K crisis might not be behind us, but ahead.
ATMs, healthcare, social security… still depend on COBOL.
A language invented in 1959.
And 95% of experts who know it will retire by 2030.
The irony? The real Y2K crisis might not be behind us, but ahead.
Hi I'm Carlo. Thanks for reading.
If you learned something new:
Follow @carlothinks for more insights like this.
If you learned something new:
Follow @carlothinks for more insights like this.
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