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Vult is a transcompiler well suited to write high-performance DSP code
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Vult is a simple and powerful language to program high-performance algorithms that may run in small microprocessors or microcontrollers. Vult is specially useful when programming Digital Signal Processing (DSP) algorithms like audio effects or synthesizers.

The Vult compiler is a transcompiler, which takes Vult code and produces plain C/C++ code that can be compiled in any platform with a C/C++ compiler, for example: Arduino or Teensy boards. Vult can also generate JavaScript that can be run directly in the browser or C/C++ that can be compiled as Pure Data externals. Code written in Vult has freedom.

Check out the documentation and tutorial in or take a look at the Wiki.


To generate C/C++ code with floating point arithmetic you have to execute vult as follows:

$ vultc -ccode infile.vult -o outfile

This will produce the files outfile.h and outfile.cpp. In order to compile and link these files you need to include in your project the files runtime/vultin.h and runtime/vultin.cpp.

To generate code with fixed point arithmetics you need to execute:

$ vultc -ccode -real fixed infile.vult -o outfile

Fixed point arithmetics are performed in q16 format; 16 bits for the integer part and 16 for the decimal.

Vult provides a few templates; for example to generate objects compatible with the Teensy Audio Library or Pure Data externals.

You can check these repositories for examples:

In the Wiki


Vult is maintained by: Leonardo Laguna Ruiz with the help of Carl Jönsson and Johan Rhodin

Logo design by: John Klimt


If you want to receive notifications for future development of this project you can join to the google group



There are three flavors the Vult compiler:

Installing with npm

You need to have node.js and npm installed.

$ npm install vult -g

This will install provide vultc command in your path. Vult is updated frequently, you can use the same command to update Vult.

The native executables can be downloaded from the releases page.

To install the node.js library use:

$ npm install vultlib

Embedding in a Web page

The compiler can be embedded in a web page providing and it provides all the functionality.

<script src=""></script>

For an example check:

Compile from Source


  • Ocaml compiler >= 4.03

Ocaml Libraries

  • containers >= 1.2
  • ppx_deriving >= 4.1
  • pla >= 1.1
  • result >= 0.99
  • [Optional] ounit >= 2.0 (to run the tests)
  • [Optional] js_of_ocaml >= 3.0 (to build the web functions)

Installing the tools

The simplest way to instal the requirements is with OPAM (

$ opam switch 4.04.2
$ opam install containers ppx_deriving pla result

Optionally to run the tests and building the web functions:

$ opam install ounit js_of_ocaml js_of_ocaml-ppx

Compiling Vult

To compile the native executable:

$ make

Compile the node.js code:

$ make jscompiler

Running tests (Linux and macOS):

$ make test
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