FoBiS.py 3.7.3

a Fortran Building System

FoBiS — Fortran Building System

Automatic dependency-resolving build tool for modern Fortran projects — no makefiles, no boilerplate.

⚡ Zero-configuration builds	🔗 Automatic dependency resolution	⚙️ Multi-compiler support	📄 fobos — the FoBiS makefile
Drop FoBiS into any Fortran project and run fobis build. It recursively scans sources, resolves all use and include dependencies, and compiles in the correct order — automatically.	Parses every source file for module definitions, use statements, and include directives. Builds and updates the full dependency hierarchy on each run, skipping up-to-date objects.	First-class support for GNU gfortran, Intel ifort/ifx, AMD flang, g95, IBM XL, NAG, PGI, NVIDIA nvfortran, and fully custom compilers. MPI, OpenMP, coarray, and coverage variants included.	A concise INI-style configuration file replaces makefiles entirely. Define multiple build modes, templates, variables, and custom rules — all in one readable file.
🚀 Parallel compilation	🌐 Fetch GitHub dependencies	🔬 Introspective doctests	🆓 Free and open source
Compile independent translation units concurrently with -j N. Dependency ordering is respected automatically; only the safe parallel frontier is compiled in parallel.	Declare external FoBiS projects in a [dependencies] fobos section. Run fobis fetch to clone, pin to branch/tag/rev, and build — then fobis build picks them up automatically.	Embed micro-unit-tests directly inside Fortran comment docstrings. FoBiS generates, compiles, and runs volatile test programs automatically — inspired by Python's doctest module, no test harness needed.	Released under the GNU GPL v3 license. Free to use, study, modify, and distribute. Contributions welcome — see the contributing guidelines.
🤖 JSON output	🧠 Claude Code skill
Pass --json to fobis build, fobis clean, or fobis fetch to get a single machine-readable JSON object instead of human-readable output. Ideal for CI scripts and AI agent workflows.	Install the bundled /fobis Claude Code skill for expert AI assistance — fobos authoring, error diagnosis, dependency setup, and more, right in your editor.

Full documentation

Why FoBiS?

Modern Fortran's module system is powerful — but tracking inter-module compilation order by hand in a makefile quickly becomes a nightmare as project size grows. Every time you add a module, rename a file, or restructure directories, the makefile needs manual updates.

FoBiS solves this completely. It parses source files on every invocation, rebuilds the dependency graph from scratch, and compiles in the correct order — with no configuration required for simple projects.

# That's it. FoBiS finds all programs, resolves all dependencies, compiles.
fobis build

For complex projects, a single fobos file in the project root replaces makefiles entirely:

[modes]
modes = debug release

[debug]
compiler  = gnu
cflags    = -c -O0 -g -Wall
build_dir = ./build/debug/

[release]
compiler  = gnu
cflags    = -c -O3
build_dir = ./build/release/

fobis build -mode release

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Projects using FoBiS

• ADAM — Accelerated fluid Dynamics on Adaptive Mesh refinement grids  |  GitHub
• BeFoR64 — Base64 encoding/decoding library for Fortran  |  GitHub
• FACE — Fortran ANSI Colors and Escape sequences  |  GitHub
• FiNeR — Fortran INI ParseR and generator  |  GitHub
• FLAP — Fortran command Line Arguments Parser  |  GitHub
• FUNDAL — Fortran UNified Device Acceleration Library  |  GitHub
• FOSSIL — FOrtran Stereo (si) Litography parser  |  GitHub
• MORTIF — MORTon Indexer (Z-order) Fortran environment  |  GitHub
• MOTIOn — Modular (HPC) Optimized Toolkit (for) IO (in fortra)n  |  GitHub
• PENF — Portability Environment for Fortran  |  GitHub
• StringiFor — Strings Fortran Manipulator with steroids  |  GitHub
• VecFor — Vector algebra class for Fortran  |  GitHub
• VTKFortran — pure Fortran VTK (XML) API  |  GitHub

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Author

Stefano Zaghi — [e-mail] · GitHub

Copyrights

FoBiS is an open source project distributed under the GPL v3 license. Anyone interested in using, developing, or contributing to FoBiS is welcome — see the contributing guidelines.

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