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Give your AS400 a modern API without rewriting what already works.
Your AS400 or IBM i system has run the business reliably for years. The problem is that nothing new can talk to it: not the e-commerce platform, not the customer portal, not the SaaS tool the team just bought. We build a secure REST API layer on top of the system you have, so modern applications can read and write its data without touching the core.
What we usually find
- Customers and sales reps calling in for order status and inventory that lives only on green screens
- Nightly batch exports to feed other systems, so every downstream tool works with yesterday's data
- A new SaaS platform purchased with no way to connect it to the system of record
- A replacement project quoted in the millions and years, for a system that otherwise works fine
- Fewer and fewer people on staff who understand the RPG programs underneath
What we build
REST API layer
Secure, documented endpoints in front of your IBM i data and business logic. Modern applications call the API; the AS400 stays the system of record and doesn't need to change.
Real-time data access
Direct reads from DB2 for i, and where it matters, calls into existing RPG or CL programs so the API uses the business rules you've already proven, rather than reimplementing them.
Web portals and app connections
Customer and partner portals for order status, inventory, quotes and invoices, plus connections to e-commerce, CRM and other SaaS platforms.
A path to AI and automation
Once the data is reachable through an API, practical automation becomes possible: flagging stalled quotes, drafting routine follow-ups, or feeding analytics, all with people reviewing the output.
Technologies
How an engagement runs
Free assessment call
We talk through what's broken, what's manual, and what the systems need to do.
System review
We look at the real system, data and files, so the plan matches what's actually there.
Build beside production
We build and test alongside your live system. Your team keeps working.
Validate and support
We run in parallel, reconcile, cut over when the numbers match, and stay on for support.
Common questions
Will this slow down or destabilize our AS400?
It shouldn't. The API layer runs on separate infrastructure and reads from the IBM i through standard database connections, with load-tested limits. We build and validate it alongside your live system before anything goes into production.
Do we have to rewrite our RPG programs?
No. The point of an API layer is to put a modern interface in front of the logic you already have. Where existing programs hold important business rules, the API can call them directly instead of duplicating that logic somewhere else.
Is this a step toward replacing the AS400 later?
It can be, but it doesn't have to be. An API layer decouples your other systems from the AS400, which makes any future migration far less risky. Many companies find that once the integration problem is solved, the pressure to replace disappears.
Start with a free assessment.
Tell us what your system is and what it needs to connect to. We'll tell you honestly whether an integration layer is the right fix, and what it would take.