Compiler Upgrades
Legacy compilers reach end-of-life. CICS or DB2 version changes force a full recompile — but source is missing.
⚑ System update blockedSource Recovery Company is the only organization on earth that recovers COBOL and Assembler source code from IBM MVS and VSE executable programs — using our patented ReSource™ technology.
Mainframe environments accumulate decades of executable programs — often outliving the source that created them. When that source goes missing, the risks are real and immediate.
Legacy compilers reach end-of-life. CICS or DB2 version changes force a full recompile — but source is missing.
⚑ System update blockedRegulators demand source-to-executable traceability. Even one unmatched module fails the audit.
⚑ Regulatory exposureAcquired application portfolios routinely include orphaned executables — critical code with no source in sight.
⚑ M&A deal riskRe-platforming to Linux or cloud requires compilable source as input. No source, no migration.
⚑ Project stalledTrue offsite DR testing exposes gaps — if source wasn't archived with executables, recovery fails.
⚑ DR plan brokenA critical production bug in a program whose source was lost. Every hour of downtime costs thousands.
⚑ Active outage riskOur process combines the patented ReSource™ engine with expert compiler analysis — producing output in as few as 2–5 business days.
Send us your IBM MVS or VSE load module securely. We handle COBOL and Assembler compiled under any historical IBM compiler version. No source, stubs, or documentation needed.
Secure transfer · NDA signed firstOur patented engine disassembles the executable, identifies compiler signatures, and reconstructs the original program logic — DATA DIVISION, PROCEDURE DIVISION, and all control structures.
Patented technology · All IBM compiler generationsOur specialists apply decades of compiler knowledge to resolve ambiguities, optimize output readability, and ensure the recovered source accurately reflects the original program's logic.
Full Recovery only · 5–10 business daysFull Recovery produces source that compiles to a load module functionally equivalent to your original. We guarantee it.
5–10 days · Guaranteed accuracyChoose the service level that matches your timeline and requirements. Both cover COBOL and Assembler on IBM MVS and VSE.
Expert-refined, thoroughly validated source code that compiles to a load module functionally equivalent to your original executable — guaranteed in writing. Our compiler specialists resolve every ambiguity and optimize for long-term maintainability.
Source code recovered directly from the ReSource™ engine, validated by compiler specialist, requires additional input such as copybooks or outdated source. Includes insertion of original naming conventions wherever feasible.
Recovery of Copybook compatible for existing source programs — requires sample executables and source code for related programs.
Developed by Fred Brandes, a globally recognized authority in IBM mainframe compiler internals, ReSource™ is the product of decades of research into the binary artifacts left by every IBM COBOL and Assembler compiler generation.
Identifies the exact IBM compiler version, compile options, date/time stamp information, and runtime library linkages — enabling precise reconstruction of original source constructs, even for compilers deprecated 30 years ago.
Reconstructs full COBOL DATA and PROCEDURE DIVISION structure — not just raw disassembly — including nested PERFORM, CALL, EVALUATE, and complex conditional control flow.
Recovered source is compiled and the resulting object module compared against your original. Behavioral equivalence is verified before delivery — not assumed.
Every engagement is covered by a signed Non-Disclosure Agreement before any executable is transmitted. Your IP and recovered source are never shared with any third party.
The most common triggers for missing COBOL source code — and how SRC's ReSource™ technology resolves each one.
| Trigger Event | Risk Without SRC | Resolved With SRC |
|---|---|---|
| CICS or DB2 version upgrade | Cannot recompile critical programs — system update indefinitely blocked | ✓ Source recovered, recompiled, upgrade proceeds on schedule |
| Internal or external regulatory audit | Source-to-executable mismatch fails compliance; regulatory penalty triggered | ✓ Missing modules recovered, source-executable parity restored, audit passed |
| Post-merger system integration | Acquired executables unmaintainable and unmigrateable; M&A value at risk | ✓ Full source inventory restored for entire acquired application portfolio |
| Cloud or Linux re-platforming | Modernization tools require compilable source — entire project stalled | ✓ Compilable COBOL delivered directly into migration tool pipeline |
| Offsite disaster recovery test | Recovery fails — source was never co-archived with executables | ✓ Source recovered and permanently added to DR archive |
| Critical production emergency | Bug in program with no source — extended outage, thousands lost per hour | ✓ Full Recovery delivers maintainable source in 1–2 business days |
Our technicians recover source code completely and accurately in far less time than it would take to rewrite any program — combining the ReSource™ patent with compiler knowledge built over three decades of serving global enterprises.
Everything enterprises need to know before engaging SRC. Not finding your answer? Contact us directly.
Mainframe COBOL and Assembler programs compiled on IBM MVS and VSE systems accumulate over decades of enterprise operation — often outliving the source libraries, version control systems, and developers that originally created them. When source code is lost, organizations face a fundamental problem: the executable load module continues to run in production, but cannot be modified, recompiled for a new compiler version, or migrated to a modern environment without first recovering the underlying source.
Source Recovery Company (SRC) was founded in 1992 and holds the only patent in the world for recovering COBOL and Assembler source code directly from IBM mainframe executable programs. The patented ReSource™ technology analyzes compiled IBM load modules, identifies compiler signatures from every historical IBM COBOL and Assembler compiler generation, and reconstructs the original program structure — including DATA DIVISION field layouts, PROCEDURE DIVISION logic, PERFORM and CALL hierarchies, CICS command-level interfaces, and DB2 embedded SQL structures.
The most common triggers for engaging SRC include IBM compiler upgrades (when a legacy compiler reaches end-of-life and all production programs must be recompiled), CICS or DB2 version migrations, regulatory and internal audit requirements demanding source-to-executable traceability, post-merger application portfolio rationalization, mainframe modernization and cloud migration projects requiring compilable source as input to automated translation tools, and production emergency response when a critical program with no available source requires immediate patching.
SRC offers three service tiers: Full Recovery provides expert-refined, guaranteed compilable source within 5–10 business days, validated for functional equivalence to the original executable; Enhanced Recovery adds original naming conventions wherever feasible within 5–15 days; and Copybook Recovery delivers compatible copybooks within 2–5 business days. All engagements are conducted under NDA with strict confidentiality.
Describe your situation and we'll respond within one business day with a detailed recovery assessment and pricing — no commitment required.