Experts of the
free and modern COBOL

Our mission is to give a second life to COBOL infrastructures

SuperBOL develops and commercialises sovereign solutions based on the GnuCOBOL open source compiler to facilitate the migration of strategic infrastructures.

Our aim is to put SuperBOL at the heart of an ecosystem by building strategic partnerships with interested parties
(public administrations, software and IT services companies…)

SuperBOL is the first French contributor to the free GnuCOBOL compiler


Revitalising applications
SuperBOL brings the agility needed for the fast evolution of COBOL applications as well as optimised performances.
Reducing costs
Open source software reduces the cost of licensing on both the compiler and the environment.
Ensuring longevity
We work with the longevity of both software and hardware in mind.
Bringing back sovereignty
For the independence of users regarding software lock-ins and non-Europeans mainframes.


SuperBOL offers a range of solutions to the challenges that organisations face when striding towards the evolution of their COBOL systems.

GnuCOBOL is an open source compiler released in 2002 under the name of OpenCOBOL. It was accepted as a GNU project between 2013 and 2015.

Migration without code modification
Supports a variety* of dialects (IBM, MicroFocus, GCOS, ...), allowing migrations without needing to modify too much of the original source code.
A mature and deployed solution
The only free compiler used in an industrial context and in public administrations (DGFiP in France).
An active community
Active and community-based development driven for an important part by SuperBOL (the first French contributor to GnuCOBOL).
Excellent portability
Good portability on all PC environments (Linux, Windows, MacOS) since it is a transpiler towards the C language.

GnuCOBOL is the most compliant COBOL compiler with evolutions of ISO standards**

  • *near 20 dialects according to the official SourceForge webpage
  • **GnuCOBOL passes 97% of NIST tests for the COBOL85 standard

SuperBOL Studio is a coding environment for COBOL on VSCode which currently features:

✓ a language server protocol (LSP) analysing COBOL code and answering developers’ requests (indentation, syntax highlighting, code navigation, error diagnostics etc).

✓ a visualisation of code coverage analysed by GnuCOBOL, allowing a clear distinction of the portions of COBOL code which are effectively executed.

Developed with the OCaml functional programming language.
Powered by academic research, it is known for its reliability and performance.



You are a COBOL developer

We develop modern tools for COBOL developers:

  • Language Server Protocol (LSP)
  • COBOL extension for VSCode
  • Code coverage and profiling for GnuCOBOL

You have specific needs? Let’s talk about it.

You manage COBOL infrastructures or work on the migration of legacy systems

We assist companies in the modernisation and the migration of COBOL infrastructures.

Strong of our experience with assisting a French public administration (DGFiP) for the exit from Bull’s obsolete GCOS mainframes with GnuCOBOL (on PC), SuperBOL develops solutions tailored to your infrastructures.

Those solutions can be integrated to the middleware of IT services companies working on migrations.

You want to assert the feasability of such a project? Let’s talk about it.

Technical support on GnuCOBOL

We fix bugs you encounter with the GnuCOBOL compiler:

  • Unrecognised syntax
  • Conflicts between ASCII and EBCDIC character encodings
  • Unexpected program behaviours

Assistance for a migration using GnuCOBOL

Since January 2022, SuperBOL actively contributes to the developement of GnuCOBOL and assists its clients in the context of a migration with GnuCOBOL.

For a migration with GnuCOBOL, SuperBOL offers:

  • Audits and proof of concept
  • Assistance in projects management

Some of our contributions for a migration with GnuCOBOL:

  • Support of the GCOS dialect on GnuCOBOL
  • Support of character sets for GCSORT
  • Support for the display of the context of errors returned by GnuCOBOL

Tooling and support on tools

We invite you to share your requests with us in order to allow our tools (such as the SuperBOL Studio) to evolve gracefully with your needs. In particular, we are able to add new features or to extend the support for our tools (handling of COBOL dialects, missing COBOL keywords or preprocessing).


"We are happy to be able to contribute to the handling of the GCOS dialect in GnuCOBOL. This dialects is widely used within our department, which has developed a large code base on GCOS COBOL. Now that the time has come to decommission GCOS systems, COBOL on Linux is our chosen target, and the GnuCOBOL compiler is its cornerstone. We extend our sincere gratitude to the OCamlPro teams [...] for their support."

Olivier Blanc (DGFiP) - Published on LinkedIn

About us

SuperBOL relies on a software company with more than 10 years of experience

SuperBOL is a team of the software company OCamlPro specialised in R&D on programming languages. This software company was created in 2011 by Fabrice Le Fessant, formerly “polytechnicien” researcher at Inria. True to its academic origin, OCamlPro’s engineers are in majority holders of PhDs in Computer Science.


  • Programming languages
    Compilation and interpretation of programs
  • Software safety
    Formal certification
  • Automatic treatment of programs
    Static analysis