This page is for source code download, and you are supposedly using Ubuntu (newer than 12.04) or CentOS (newer 7)as your host OS.
Please execute the following command to update.
For Ubuntu system:
$ sudo apt-get update; sudo apt-get upgrade -y; sudo apt-get install -y wget git
For CentOS system：
$ sudo yum update -y; sudo yum install -y wget git
you can just do following step if you are updating the latest version.
$ git clone https://github.com/open-estuary/estuary.git
Estuary : git clone https://github.com/open-estuary/estuary.git Distro-repo : git clone https://github.com/open-estuary/distro-repo.git Linux Kernel : git clone https://github.com/open-estuary/kernel.git