You can install the package with the command below, depending on your os:
$ yum install (see available packages in table below)
$ dnf install (see available packages in table below)

HHVM

HHVM is an open-source virtual machine designed for executing programs written in Hack and PHP. HHVM uses a just-in-time (JIT) compilation approach to achieve superior performance while maintaining the development flexibility that PHP provides.

Available Packages:

Package Version
ulyaoth-hhvm 3.17.3
ulyaoth-hhvm-lts3.3 3.3.7
ulyaoth-hhvm-lts3.6 3.6.6
ulyaoth-hhvm-lts3.9 3.9.10
ulyaoth-hhvm-lts3.12 3.12.14
ulyaoth-hhvm-lts3.15 3.15.7
ulyaoth-hhvm-lts3.18 3.18.1

Supported Operating Systems:

Operating Systems Versions
Amazon Linux latest
CentOS 7 (EPEL)
Fedora 19, 20, 21, 22, 23, 24, 25 (Depends on HHVM version)
Oracle Linux 7 (EPEL)
Red Hat 7 (EPEL)
Scientific Linux 7 (EPEL)

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