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@catalin-hritcu catalin-hritcu released this Jun 26, 2019

A preview for an upcoming major release in preparation for several summer schools. Precise release notes coming up in the non-alpha release, but you can already have a look at:

Assets 5

@tahina-pro tahina-pro released this May 17, 2018 · 10351 commits to master since this release

A large number of people contributed to this release: thanks to all!

Here are a few highlights:

Main new features

  • Meta-F*: A metaprogramming and tactic framework, as described in this report. Code samples are in examples/tactics, examples/native_tactics and the FStar.Tactics and FStar.Reflection libraries. Many people contributed a lot to this work, especially Guido Martinez.

  • Improved type inference with two-phase typechecking: We now build verification conditions for a program after a first phase of type inference. This improves inference of implicit arguments and reduces our trust in the type inference. Thanks to Aseem Rastogi!

  • Caching typechecked modules: F* emits ".checked" files, an on-disk representation of a typechecked module that can be read back later. This significantly reduces the time to load a module's dependences.

Many other improvements

A sampling of improvements across the entire tool chain:

  • Resolving several syntactic ambiguities in the parser

  • A correct pretty printer for surface terms, using fstar --indent

  • A new dependence analysis to support incremental compilation for larger projects

  • Overhauling the higher order unification algorithm, both in the representation of meta-variables and in the handling of unfolding, leading to significant performance and robustness improvements (see

  • Automatic generation of interfaces for modules and tighter enforcement of abstraction boundaries (see's-interface)

  • Improvements to the SMT encoding, removing axioms that lead to performance problems and reducing brittleness related to optimizations in the encoding, notably shallow vs deep encodings

  • Improved type-based erasure for extraction

  • Several new and improved libraries, including a revised treatment of footprints for Low* programs, in FStar.Modifies

  • And work by many people in Project Everest whose use of F* drove a lot of the work in this release.

  • Plus many other improvements and changes as described in

  • And 180 closed github issues

Assets 5

@danelahman danelahman released this May 4, 2018 · 10894 commits to master since this release

A preview for an upcoming major release in preparation for several courses and tutorials.

This brings lots of improvements:

  • two-phase type checking (towards disentangling type checking from checking of verification conditions), more robust wrt. inference of implicit arguments
  • extraction to OCaml preserves the structure of let-bindings
  • extraction now erases all pure unit functions, lemmas and ghost functions
  • and many many more, see for more details.
Assets 5

@nikswamy nikswamy released this Aug 23, 2017

This is another big release with lots of changes and new features compared to v0.9.4.0

Main new features

  • Proofs by reification (see this paper)
  • A revision of the libraries based on a new formal account of monotonic state (see this paper)
  • Extraction of programs with user-defined effects
  • Experimental support for tactics
  • New IDE protocol and new IDE features: autocompletion, evaluation, real-time syntax checking, jump-to-definition, type-at-point, etc.

Changes and other improvements

  • A reorganization of the library and a single fstarlib.cmxa against which to link all F* programs compiled to OCaml (this change is incompatible with previous versions of F*)
  • A new printer of source terms
  • Revised error reporting from failed SMT queries
  • Improved support for separate compilation via a binary format for checked modules
  • Fixed a ton of bugs (179 closed GitHub issues)
Assets 5
Jul 10, 2017
Version of F* master as witnessed at the '17 summer school in Nancy

@catalin-hritcu catalin-hritcu released this Feb 2, 2017

This is a big release with lots of important changes compared to v0.9.2.0 exactly a year ago:

  • Predicative hierarchy of universes with universe polymorphism
  • Uniform syntax between expressions and types allowing rich type-level computation
  • Dijkstra Monads for Free (
  • Extraction to C via KreMLin (
  • New parser based on Menhir
  • New pretty printer for surface syntax and fstar --indent
  • Changed default effect to Tot
  • Strict positivity check for inductives
  • New synatax for inductive type projectors and discriminators
  • Better semantics for module open and support for local opens
  • Better dependency analysis
  • Better error locations for Z3 failures
  • Replaced Z3 timeouts with machine independent resource limits
  • Cleaned up libraries and examples (a bit)
  • Improvements to interactive mode
  • Docker builds
  • Fixed a ton of bugs (262 closed GitHub issues)
Assets 5

@catalin-hritcu catalin-hritcu released this Sep 7, 2016 · 21897 commits to master since this release

This is a quick beta release for the Bucharest Crypto School ( so no time for writing release notes now. Still, this release is a huge step forward compared to the previous.

On Windows you will need the libgmp-10.dll library. You might already have it in your path if you use cygwin, otherwise an easy installation option is to install git-for-windows:

Assets 5

@beurdouche beurdouche released this Feb 3, 2016

This release includes a number of changes:

  • automatic dependency analysis using fstar --dep (still experimental)
  • consistent renaming of standard library modules
  • improvements to contrib/CoreCrypto
  • added bounded integers
  • int extracted to multi-precision now
  • nubuild improvements
  • better documentation
  • cooler Wysteria example
  • new first-order unification example
  • fixes for many other issues
Assets 5
Feb 1, 2016

@catalin-hritcu catalin-hritcu released this Oct 13, 2015 · 24761 commits to master since this release

Just a re-release of v0.9.1 with minor changes.

Assets 5
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