Engineering

Mainframe Developer Interview Questions

The questions you're most likely to face in a Mainframe Developer interview — behavioral, technical, and role-specific. Then practise them out loud with a free AI mock interview.

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Behavioral & fit

  1. 1.Tell me about yourself and why you're targeting this role.
  2. 2.Describe a project you're most proud of. What was your specific contribution?
  3. 3.Tell me about a time you missed a deadline or failed. What did you learn?
  4. 4.How do you prioritise when everything feels urgent?
  5. 5.Describe a disagreement with a teammate and how you resolved it.

Technical — core Mainframe Developer skills

  1. 1.Walk me through how you've applied COBOL in a real mainframe developer project.
  2. 2.Walk me through how you've applied JCL in a real mainframe developer project.
  3. 3.Walk me through how you've applied VSAM in a real mainframe developer project.
  4. 4.Walk me through how you've applied DB2 in a real mainframe developer project.
  5. 5.Walk me through how you've applied CICS in a real mainframe developer project.

Tools & technologies

  1. 1.What's your experience with COBOL, and when would you choose it over an alternative?
  2. 2.What's your experience with JCL, and when would you choose it over an alternative?
  3. 3.What's your experience with DB2, and when would you choose it over an alternative?
  4. 4.What's your experience with CICS, and when would you choose it over an alternative?

Role-specific

  1. 1.What does success look like in a Mainframe Developer role in the first 90 days?
  2. 2.How do you stay current with changes in engineering?
  3. 3.Describe how you'd approach a typical problem a Mainframe Developer faces day to day.

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Company-specific interview questions

Round-by-round processes, difficulty, and what each interviewer assesses.

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