off-the-stack
cd ~/careers
Core systems / legacyaka "Mainframe Eng"

Mainframe / COBOL Engineer

The systems running the world's money won't die — and the people who maintain them are retiring.

Entry
$75k
Mid
$110k
Senior
$155k+
Demand
Steady

Banks, insurers, airlines, and governments still run their most critical transactions on mainframes, largely in COBOL, and that code isn't going anywhere. The generation that wrote it is retiring faster than anyone is replacing them, which makes a young engineer willing to learn this 'dead' technology weirdly, durably valuable.

The myth

It's obsolete and there's no future in it.

The reality

Mainframes still process the majority of the world's card transactions. The work is mission-critical, well paid, and increasingly involves modern tooling, APIs, and integration around the legacy core.

cat ./what_you_actually_do.md

  • Maintain and extend COBOL systems that run banking, insurance, and government transactions.
  • Work with z/OS, JCL, CICS, and DB2 — the mainframe stack the modern world quietly depends on.
  • Wrap legacy cores with APIs so newer systems can talk to them.
  • Support careful, high-stakes modernization without breaking the thing that can't go down.
  • Become the rare person who actually understands how the money moves.

cat ./why_underrated.md

It's the ultimate anti-trend: a 'dead' language on 'obsolete' hardware that students are practically told to avoid. But the reality is a demographic cliff — the COBOL workforce is retiring en masse while the systems they built remain irreplaceable, because rewriting a bank's core is a decade-long, billion-dollar risk almost no one will take. That mismatch makes scarcity your superpower. Learn what everyone else dismisses, and you become very hard to replace in industries that pay well and never lay off their core systems team.

grep -i 'good fit' ./who.md

  • Contrarians comfortable being the youngest person in the room by decades.
  • People who value extreme job security and don't need to chase trends.
  • Methodical engineers who respect high-stakes, can't-fail systems.

cat ./pay.md

The scarcity premium is the whole point. Specialist mainframe contractors — especially in banking and insurance — command very high day rates, and full-time senior engineers reach $150k+ precisely because almost no one under 40 can do the job.

./break_in.sh

  1. Take IBM's free mainframe training

    IBM's Z Xplore and the Master the Mainframe materials are free and give you real hands-on z/OS access.

  2. Learn COBOL and JCL

    They're more approachable than their reputation. Build a few small batch programs to prove it to yourself.

  3. Target banks, insurers, and government

    These are the employers desperate for fresh blood on their core systems — many run dedicated trainee programs.

  4. Lean into the modernization angle

    Pair COBOL with APIs and integration skills and you become the bridge between the old core and the new world.

tail -f ./a_day.log

  • 09:00A nightly batch job abended; read the JCL and dump to find the bad record.
  • 11:00Modify a COBOL program handling premium calculations, with extreme care.
  • 14:00Expose a CICS transaction through a REST API for a new mobile feature.
  • 16:00Pair with a soon-to-retire veteran to document tribal knowledge before it walks out the door.

ls ./toolbelt

  • COBOL
  • JCL
  • z/OS
  • CICS
  • DB2
  • APIs around the core