r/mainframe is a subreddit with 11k members. The most common kinds of discussions are advice requests and opportunities, and the community frequently discusses mainframe, cobol, z/os, career, and job.
Discussion of all things Mainframe - hardware & software, programming & support.
Popular Themes in r/mainframe
#1
Advice Requests
: "Is Mainframe valuable at the start of the career?"
21 posts
#2
Opportunities
: "Good idea to work on z/OS Mainframe Support?, got an offer"
5 posts
#3
Solution Requests
: "Mainframe Veteran, how do you actually find documents and solutions to your day-to-day problems? "
4 posts
#4
Pain & Anger
: "One must ask what's wrong with COBOL?"
3 posts
#5
Ideas
: "Kyndryl zCloud"
1 post
#6
Money Talk
: "Did I make a good deal?"
1 post
Popular Topics in r/mainframe
#1
Mainframe
: "Looks like the Mainframe reality really hit the DOGE team in the face. A true COBOL Mainframe guy statement: "they cannot change the system""
218 posts
#2
Cobol
: "Looks like the mainframe reality really hit the DOGE team in the face. A true Cobol Mainframe guy statement: "they cannot change the system""
57 posts
#3
Z/os
: "Is Z/os still worth learning?"
42 posts
#4
Career
: "Is Mainframe valuable at the start of the Career?"
29 posts
#5
Job
: "New Rule Proposal: All Job posts must have Job description and salary range in the original post."
27 posts
#6
Ibm
: "Build your own Mainframe - Ibm z17 & LinuxONE 5 Lego"
20 posts
#7
Learning
: "Any advice for Learning REXX in a year?"
14 posts
#8
Jcl
: "How to add Sequence no in a file through a Jcl | All About mainframes"
13 posts
#9
Modernization
: "Modernization rant"
11 posts
#10
Migration
: "VSE / VM tape Migration success!"
11 posts
Member Growth in r/mainframe
Yearly
+2k members(22.8%)
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About
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Last updated: June 25, 2026