Mainframe replacement

Your COBOL runs.
IBM goes away.

True/z compiles your COBOL to native code and runs it on commodity hardware. VSAM datasets, JCL, CICS transactions, DB2 queries — all working. No rewrite. Dedicated instance. Spot cloud pricing.

458/458 NIST CCVS85
135/135 SQL V6.0
22 test suites passing
0 lines rewritten

The rewrite failed. Again.

Every mainframe modernization project promises the same thing: rewrite the COBOL in Java, migrate the data, retire the iron. Three years and $40M later, the mainframe is still running because the rewrite can't pass the conformance tests the mainframe passes on day one.

The IBM tax

MIPS-based licensing. Hardware refresh cycles. IBM Global Services renewals. The cost only goes up.

The talent cliff

The average COBOL programmer is 55. They're retiring. The rewrite-to-Java strategy assumes you'll hire replacements. You won't.

The failed rewrites

Every bank, insurer, and agency has a failed modernization in their past. $20M–$100M spent. Mainframe still running.

Don't rewrite. Replace.

True/z transpiles your COBOL to native machine code and runs it on standard x86 servers. Your programs execute at native speed. Your VSAM datasets work. Your JCL submits jobs. Your CICS transactions process. Your DB2 queries return the same results.

# Transpile a COBOL program
$ truez transpile PAYROLL.CBL
Compiling PAYROLL → payroll.zelf (native x86-64)
VSAM: EMPLOYEE-FILE (KSDS), PAYROLL-HIST (ESDS)
CICS: MAP PAYMENU (BMS compiled)
✓ 0 errors, 0 warnings

# Run the NIST conformance suite
$ truez test --suite ccvs85
PASS: 458/458 tests
$ truez test --suite sql-v6
PASS: 135/135 tests

Spot pricing. No contract.

Pay for what you use. No three-year enterprise agreements. No per-MIPS licensing. No hardware refresh cycles. Cancel anytime.

IBM z/OS

$137–308/core-hr

MIPS-based licensing. Peak R4HA sets your bill for the entire month. One bad batch night = 30 days of charges at peak rate. 3-year minimum. Hardware lease on top.

True/z

50% less

Consumption pricing on dedicated instances. Pay per vCPU-hour, only when jobs are running. Scale up for batch windows, scale down overnight. No peak penalty. No contract. No minimums.

All Rust. No C in the critical path.

True/z is built entirely in Rust — the transpiler, the runtime, the storage engine, the transaction monitor, the security subsystem. No buffer overflows, no use-after-free, no data races in the code that handles your data.

Memory safe

The entire platform — from the COBOL runtime to the VSAM engine to the crypto — is Rust with compile-time memory safety guarantees.

Auditable

~3,400 unsafe sites, all at the hardware boundary. Every one is grep-able. Compare to millions of lines of C in z/OS.

Erasure coded

Reed-Solomon K+M erasure coding with CRUSH placement. Your data survives disk failures without RAID overhead.

Run your COBOL on True/z.

Spin up a dedicated instance. Upload your programs. Transpile them. Run the conformance tests yourself. Your code never leaves your instance. No sales call. No NDA. Just proof.

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