Mainframe-compatible environments available:
Need a mainframe-compatible environment for your team or project? We offer:
– Training seats
– Dev seats
– Project test sandboxes
– Dedicated single-tenant instances (hosted, BYOC, or on-prem)
– Demo estates
– Modernization rehearsal mirrors
– The conformance bench

Email support@cobolstack.com to find the right setup for you.

For courses:
Enroll now!
Course info: https://www.cobolstack.com/courses/cs100/

Get your COBOLStack completion certificate

Finished the course? You can earn a certificate of completion from cobolstack.com.

Here’s how:
1. Request a userid using the link on the login screen at cobolstack.com
2. Complete the hands-on exercises for every session
3. Email support@cobolstack.com with:
– Your name and userid
– The job numbers for the exercises you completed in each session

We’ll verify your work and send your certificate by email.

Corporate training available:
We also run corporate training with live instructors — mainframe and AS/400 courses delivered to your team on our hands-on environment. Email support@cobolstack.com to discuss your team’s needs.

Questions? Drop them in the comments or email support@cobolstack.com.

🔗 Try it yourself:
Steelframe Mainframe-compatible environment: In browser, open https://steelframe.cobolstack.com
Steelframe Developer (WIndows-based environment): In browser, open https://steelframe.cobolstack.com/studio
Connect thru Telnet3270 client like wc3270 or PCOMM: configure IP 13.212.85.240 port 23

Steelframe Mid-range-compatible environment: In browser, open https://steelframex.cobolstack.com
Connect thru Telnet5250 client like PCOMM: configure IP 18.138.249.167 port 2323

Note: these are demo environments for training, testing, and development purposes only — not production. Accessed over HTTP/IP, so your browser may show a security warning; that’s expected.

DISCLAIMER:
This software is an independent, compatible reimplementation, not affiliated with, sponsored by, or endorsed by IBM. IBM, IBM i, AS/400, and DB2 are trademarks or registered trademarks of International Business Machines Corporation, referenced only to identify compatibility. All other trademarks are the property of their respective owners.

Who we are
Our founder and our team are mainframe professionals with over twenty years of experience. That experience is broad by design: DevOps, application development and modernization, on the estates that still run banks and the businesses around them. The people who teach here are the same people who have spent careers building, running and modernizing these systems — so a bootcamp session on JCL restarts, or an advisory conversation about a modernization seam, comes from practice rather than slides.

We are deliberately small. You deal with the senior people, from the first conversation through delivery, and we take on the work we can do properly.

What we do
Bootcamps and corporate training. Cohort bootcamps that take new hires from zero to productive on the mainframe and IBM i, and corporate programmes shaped to your stack — every session ending in a lab on the trainee’s own environment. See the corporate training page and the course catalog.

Additional services on request. Beyond training, we support clients with advisory and hands-on help on their estates. Tell us what you are dealing with and we will say plainly whether it is something we do — our engagement catalog and capability page are the honest starting points.