9.1.4 A Timeline of Selected Guile Releases

guile-i — 4 February 1995

SCM, turned into a library.

guile-ii — 6 April 1995

A low-level module system was added. Tcl/Tk support was added, allowing extension of Scheme by Tcl or vice versa. POSIX support was improved, and there was an experimental stab at Java integration.

guile-iii — 18 August 1995

The C-like syntax, ctax, was improved, but mostly this release featured a start at the task of breaking Guile into pieces.

1.0 — 5 January 1997

#f was distinguished from '(). User-level, cooperative multi-threading was added. Source-level debugging became more useful, and programmer’s and user’s manuals were begun. The module system gained a high-level interface, which is still used today in more or less the same form.

1.1 — 16 May 1997

1.2 — 24 June 1997

Support for Tcl/Tk and ctax were split off as separate packages, and have remained there since. Guile became more compatible with SCSH, and more useful as a UNIX scripting language. Libguile could now be built as a shared library, and third-party extensions written in C became loadable via dynamic linking.

1.3.0 — 19 October 1998

Command-line editing became much more pleasant through the use of the readline library. The initial support for internationalization via multi-byte strings was removed; 10 years were to pass before proper internationalization would land again. Initial Emacs Lisp support landed, ports gained better support for file descriptors, and fluids were added.

1.3.2 — 20 August 1999

1.3.4 — 25 September 1999

1.4 — 21 June 2000

A long list of lispy features were added: hooks, Common Lisp’s format, optional and keyword procedure arguments, getopt-long, sorting, random numbers, and many other fixes and enhancements. Guile also gained an interactive debugger, interactive help, and better backtraces.

1.6 — 6 September 2002

Guile gained support for the R5RS standard, and added a number of SRFI modules. The module system was expanded with programmatic support for identifier selection and renaming. The GOOPS object system was merged into Guile core.

1.8 — 20 February 2006

Guile’s arbitrary-precision arithmetic switched to use the GMP library, and added support for exact rationals. Guile’s embedded user-space threading was removed in favor of POSIX pre-emptive threads, providing true multiprocessing. Gettext support was added, and Guile’s C API was cleaned up and orthogonalized in a massive way.

2.0 — 16 February 2010

A virtual machine was added to Guile, along with the associated compiler and toolchain. Support for internationalization was finally reimplemented, in terms of unicode, locales, and libunistring. Running Guile instances became controllable and debuggable from within Emacs, via Geiser. Guile caught up to features found in a number of other Schemes: SRFI-18 threads, module-hygienic macros, a profiler, tracer, and debugger, SSAX XML integration, bytevectors, a dynamic FFI, delimited continuations, module versions, and partial support for R6RS.

2.2 — 15 March 2017

The virtual machine and introduced in 2.0 was completely rewritten, along with much of the compiler and toolchain. This speeds up many Guile programs as well as reducing startup time and memory usage. Guile’s POSIX multithreading was improved, stacks became dynamically expandable, the ports facility gained support for non-blocking I/O.

3.0 – January 2020

Guile gained support for native code generation via a simple just-in-time (JIT) compiler, further improving the speed of its virtual machine. The compiler itself gained a number of new optimizations: inlining of top-level bindings, better closure optimization, and better unboxing of integer and floating-point values. R7RS support was added, and R6RS support improved. The exception facility (throw and catch) was rewritten in terms of SRFI-34 exception handlers.