Exakat is a PHP static analyzer. It relies on PHP to lint and tokenize the target code; a graph database to process the AST and the tokens; a SQLITE database to store the results and produce the various reports.

Exakat itself runs on PHP 7.0 and more recent, with a short selection of extensions.

exakat architecture

Source code is imported into exakat using VCS client, like git, SVN, mercurial, tar, zip, bz2 or even symlink. Only reading access is required.

At least one version of PHP have to be used, and it may be the same running Exakat. Extra versions are used to provide linting reports. Only one version is used for analysis.

The gremlin server is used to query the source code. Once analyzes are all finished, the results are dumped into a SQLITE database and the graph may be removed. Reports are build from this database.


Exakat relies on several parts. Some are necessary and some are optional.

Basic requirements :

  • exakat.phar, the main code.
  • Neo4j and gremlin : exakat uses this graph database, with the Gremlin 3 plugin.
  • PHP 7.0 or later to run. This version requires curl, hash, phar, sqlite3, tokenizer, mbstring and json.

Optional requirements : * PHP 5.2 to 7.2 for analysis. Those versions only require the ext/tokenizer extension. * VCS (Version Control Software), such as Git, SVN, bazaar, Mercurial. They all are optional, though git is recommended. * Archives, such as zip, tgz, tbz2 may also be opened with optional helpers.

OS requirements : Exakat has beed tested on OSX, Debian and Ubuntu (up to 14.04). Exakat should work on Linux distributions, may be with little work. Exakat hasn’t been tested on Windows at all.

Quick installation with OSX

Paste the following commands in a terminal prompt : the first script download the exakat.phar, and the second sets up Gremlin 3 on Neo4j 2.3. PHP 7.0 or more recent, curl, homebrew are required.

mkdir exakat
cd exakat
curl -o exakat.phar
curl -sL | sh
php exakat.phar doctor

Quick installation with Debian/Ubuntu

Paste the following commands in a terminal prompt : the first script download the exakat.phar, and the second sets up Gremlin 3 on Neo4j 2.3. PHP 7.0 or more recent, wget are expected.

mkdir exakat
cd exakat
wget -O exakat.phar
wget -qO- | sh
php exakat.phar doctor

Installation guide with Docker

There are several ways to install Exakat with docker :

  • No docker at all. Then, check a bare-bone install with OSX, Debian or Vagrant.
  • With the various versions of PHP on a container : convenient to have several versions of PHP without installing them.
  • With Neo4j on a container. Convenient to mask the Gremlin server.
  • All exakat on a container. All packaged in one place.

Installation guide with Docker : all on the container

Installation with docker is easy, and convenient. It hides the dependency on the graph database, and keeps all files in the ‘projects’ folder, created in the working directory.

Currently, Docker installation only ships with one PHP version (7.0).

  • Install Docker
  • Start Docker
  • Pull exkat :
docker pull exakat/exakat
  • Run exakat :
docker run -it -v $(pwd)/projects:/usr/src/exakat/projects --rm --name my-exakat exakat/exakat version
  • Init a project :
docker run -it -v $(pwd)/projects:/usr/src/exakat/projects --rm --name my-exakat exakat/exakat init -p <project name> -R <vcs_url>

_Please note_: The init command usually makes a local clone of your repository. In case you want to analyse a private repository for which you need an SSH key, init will fail silently on the cloning process. Before running the project command below, run:

cd projects/<project name> git clone <git_url> code

If you don’t use git, or don’t want to use version control, make sure that your project code ends up in projects/<project name>/code for Exakat to work correctly.

  • Run exakat :
docker run -it -v $(pwd)/projects:/usr/src/exakat/projects --rm --name my-exakat exakat/exakat project -p <project name>

You may simply run any exakat command by prefixing it with the following command :

docker run -it -v $(pwd)/projects:/usr/src/exakat/projects --rm --name my-exakat exakat/exakat

You may also create a handy shortcut, by creating an script and put it in your PATH :

cat 'docker run -it -v $(pwd)/projects:/usr/src/exakat/projects --rm --name my-exakat exakat/exakat $1' > /etc/local/sbin/
chmod u+x  /etc/local/sbin/
./ version

Installation with Gremlin server on Docker

It is possible to install Exakat as a phar or source code, and the Gremlin server as a docker image.

This installation script presume that docker is installed and running.

mkdir exakat
cd exakat
mkdir -p neo4j/scripts
curl -o exakat.phar
chmod u+x exakat.phar
php exakat doctor

sed -i.bak -e "s/neo4j_host     = '';/neo4j_ip = '`docker-machine ip`';/" config/exakat.ini
sed -i.bak -e "s/neo4j_port     = '7474';/neo4j_port     = '7777';/" config/exakat.ini
sed -i.bak -e "s/;loader = CypherG3/loader = CypherG3/" config/exakat.ini
sed -i.bak -e "s/loader = Neo4jImport/;loader = Neo4jImport/" config/exakat.ini
rm config/exakat.ini.bak

docker pull exakat/gremlin4neo4j
docker run --publish=7777:7777 \
        -v $(pwd)/projects/.exakat:$(pwd)/projects/.exakat \
        -v $(pwd)/neo4j/scripts:/usr/src/gremlin/neo4j/scripts \
        -d exakat/gremlin4neo4j

You may now run an exakat project. Restart the docker image to run another project.

Installation With PHP On Docker

It is possible to install various PHP versions, provided as docker images. Check the docker PHP container on the docker web site to find the available containers.

In the config/exakat.ini file, mention the PHP version with this format :

; config/exakat.ini
php56 = php:5.6
php71 = php:7.1

Installation guide with Composer

Exakat is available on packagist. After the composer installation, it initially requires the installation of the graph database. Once gremlin installed, it is rarely updated.

The documentation is written with OSX as target.

mkdir exakat
cd exakat
composer require exakat/exakat
php vendor/bin/exakat doctor
curl -sL | sh
php vendor/bin/exakat init -p x

Installation guide with Vagrant and Ansible

Installation list

The exakat-vagrant repository contains an automated install for exakat. It installs everything in the working directory, or the system. Vagrant install works with Debian and Ubuntu images (not yet 16.04, though). Other images may be usable, but not tested.


You need the following tools :

Most may easily be installed with the local package manager, or with a direct download from the editor’s website.

Install with Vagrant and Ansible

git clone
cd exakat-vagrant
// Review the Vagrant file to check the size of the virtualbox
vagrant up --provision
vagrant ssh

You are now ready to run a project.

Installation guide for Debian/Ubuntu

These is the installation guide for a Debian server. This also serves as general installation guide.


  • Java 1.8
  • Neo4j 2.3.*
  • Gremlin 3.2 plugin
  • PHP
  • exakat.phar

Debian install


This list of apt-get will install several needed libs for the installation.

apt-get install gcc make libc-dev libtool re2c autoconf automake git curl  libcurl3 libcurl3-dev  php5-curl
apt-get update
apt-get upgrade
apt-get clean

Java install

Java 8 is needed. Java 7 might work but is not recommended.

The following shell code install Java 8. Root privileges are needed.

## You'll need to run this as root
echo "deb trusty main" > /etc/apt/sources.list.d/webupd8team-java.list
echo "deb-src trusty main" >> /etc/apt/sources.list.d/webupd8team-java.list
apt-key adv --keyserver --recv-keys EEA14886
apt-get update
apt-get install oracle-java8-installer

# Check
java -version


Download Neo4j 2.3.* version (currently, 2.3.9). Neo4j 2.2 is not supported anymore. Neo4j 3.0 has no support for Gremlin at the moment (2017-03-01)


tar -xvf neo4j-community-2.3.9-unix.tar.gz
mv neo4j-community-2.3.9 neo4j

In the neo4j folder, update the server configuration. The configuration is in the neo4j_home/conf/ :

Activate the gremlin plugin.

# add this line below the above one

You may also disable authentication. If not, do not forget to update the config/exakat.ini file, with the right credential.

Gremlin plug-in

Exakat uses gremlin plug-in for Neo4j. Follow the install instructions there.

Make the following changes in the following files :

  • tinkerpop3/pom.xml
    • change the tinkerpop-version tag from 3.1.0-incubating to 3.2.0-incubating

Then, in command line :

git clone gremlin
cd gremlin
mvn clean package -Dtp.version=3
unzip target/ -d ../neo4j/plugins/gremlin-plugin
cd ../neo4j
bin/neo4j restart

Various versions of PHP

You need one version of PHP (at least) to run exakat. This version needs the curl, hash, Semaphore , tokenizer and sqlite3 extensions. They all are part of the core.

Extra PHP-CLI versions allow more checks on the code. They only need to have the tokenizer extension available.

Exakat recommends PHP 7.1.0 (or latest version) to run Exakat. We also recommend the installation of PHP versions 5.2, 5.3, 5.4, 5.5, 5.6, 7.1 and 7.2 (aka php-src master).

To install easily various versions of PHP, use the ondrej repository. Check The main PPA for PHP (5.6, 7.0, 7.1). You may also check the dotdeb repository, at dotdeb instruction.


Download the exakat.phar archive from and place it in the exakat folder.


From the commandline, run php exakat.phar doctor. This will check if all of the above has be correctly run and will report some diagnostic.

Optional installations

By default, exakat works with Git repository for downloading code. You may also use

The binaries above are used with the init and update commands, to get the source code. They are optional.