Licensing

The released ry program is licensed under the GNU General Public License, version 2 or later (GPL-2.0-or-later), the same terms as GNU R.

The reason is that parts of ry’s runtime are translations of GNU R’s C code, such as its distribution functions, random number generators and plotmath, so the crates that contain them, and every crate that links one, are GPL. The tooling crates that do not link the runtime (the parser, formatter, type checker and editor features) stay under the permissive Universal Permissive License (UPL-1.0), so they remain reusable as libraries in any project. The C headers that packages compile against are LGPL-2.1-or-later, as R’s own headers are, so a compiled package may choose its own licence. This is the arrangement R itself uses, with GPL code behind LGPL headers, and it resembles FFmpeg, whose build becomes GPL when its GPL parts are enabled.

Some Rust crates that ry links are Apache-2.0, which is compatible with version 3 of the GPL but not version 2, so the ry binary as a whole is passed on under GPL-3.0-or-later. ry’s own sources remain available under version 2 or later.

The full texts are in LICENSE, and each release archive carries it. The source code of a release is its git tag.

Every part and its licence

Part	Licence
interp, the R interpreter	GPL-2.0-or-later
jit, the compiler	GPL-2.0-or-later
libr, R’s C API as a libR shared library	GPL-2.0-or-later
loader, the package loader, with its R scripts	GPL-2.0-or-later
ry-lang (crates/ry), the ry program, with its R scripts	GPL-2.0-or-later
the fuzz targets in fuzz/	GPL-2.0-or-later
the C headers in crates/libr/include	LGPL-2.1-or-later
syntax, semantics, format, ide	UPL-1.0
heap, table, sniff, rdb	UPL-1.0
rcmd, with its install.R, and repl	UPL-1.0
oracle, the differential test harness	UPL-1.0
the type stubs in types/, the tools and scripts	UPL-1.0
the docs site in docs/	UPL-1.0 (its Geist fonts are OFL-1.1)
the VS Code and Zed extensions in editors/	MIT
patches/iana-time-zone	MIT OR Apache-2.0, as upstream
third-party crates and C libraries in ry	their own; see THIRD_PARTY_NOTICES

A crate is GPL exactly when it contains code translated from GNU R or depends on a crate that does. repl embeds the built libR as bytes but does not link it, so it stays UPL-1.0. A VS Code extension built for one platform bundles the ry binary, so its LICENSE holds the MIT licence for the extension’s own code followed by ry’s LICENSE, and it carries THIRD_PARTY_NOTICES.

just notices regenerates THIRD_PARTY_NOTICES from Cargo.lock, the crates’ licence files and the provenance headers below, and just notices --check fails when the file is stale or a crate’s license field breaks the rule above.

Code derived from GNU R

Each file below starts with a header that names its GNU R sources and keeps their copyright lines. All of them are in crates/interp/src.

File	GNU R sources
rmath.rs	src/nmath/: toms708.c, pnorm.c, qnorm.c, ptukey.c, qtukey.c, pnt.c, pt.c, qt.c, qbeta.c, chebyshev.c, gamma.c, lgamma.c, pgamma.c, cospi.c, stirlerr.c, bd0.c, dbinom.c, dpois.c
distributions.rs	src/nmath/: rgamma.c, rbeta.c, rpois.c, rbinom.c, rhyper.c
random.rs	src/nmath/snorm.c, src/nmath/sexp.c, src/main/RNG.c, src/main/random.c
arith.rs	src/main/complex.c (complex asin, acos, atan)
plotmath.rs	src/main/plotmath.c
graphics.rs	src/library/graphics/src/plot3d.c (contour labels, persp)
graphics_engine.rs	src/main/xspline.c
stats_tests.rs	src/library/stats/src/swilk.c, src/library/stats/src/prho.c
stats_nlm.rs	src/appl/uncmin.c
stats_optimize.rs	src/appl/integrate.c, src/library/stats/src/optimize.c

stats_lbfgsb.rs follows the BSD-licensed L-BFGS-B 3.0 reference code and keeps its notice, and the font metrics in graphics.rs and graphics_render.rs come from Adobe’s AFM files under Adobe’s terms; both notices are in THIRD_PARTY_NOTICES. Base R’s own R code is not part of ry: the runtime reads it from the GNU R installation at run time.