The BTG Organization uses the Gitian build process, which was developed for Bitcoin, to provide trusted, digitally-signed binaries for download in the official BTCGPU repositories. These are also the links in the bitcoingold.org download pages.
From https://gitian.org/ :
Gitian is a secure source-control oriented software distribution method. This means you can download trusted binaries that are verified by multiple builders.
Gitian uses a deterministic build process to allow multiple builders to create identical binaries. This allows multiple parties to sign the resulting binaries, guaranteeing that the binaries and tool chain were not tampered with and that the same source was used. It removes the build and distribution process as a single point of failure.
In plain English: the process lets a bunch of independent people (“Builders”) compile the source code and confirm that the resulting application is always the same. Then they can sign their builds with their personal cryptographic keys for other Builders to confirm.
It’s a multi-step process and requires a fair bit of computer savvy, and experience on Linux and as a developer is extremely helpful. When a group of people can confirm that their build result is bit-for-bit identical to everyone else’s, it enhances safety for the whole community.
Aaron van Wirdum wrote an excellent article about the how and why of Gitian Building in Bitcoin Magazine.
BTG has been built with the Gitian build process since version 0.15.0.2 in January of 2018; see https://bitcoingold.org/bitcoin-gold-wallet-v0-15-0-2-release/.
High-level steps/requirements if you want to be a BTG Gitian Builder:
- Have or make a GitHub account
- Have or make a PGP key on public keyservers
- Fork the BTCGPU/gitian.sigs repo into your account
- Run a clean Ubuntu install or use a pre-made VM
a. Configure git to talk to GitHub with SSH
b. Clone your gitian.sigs repo yourself
- Run the build (takes hours)
- Execute the signing process
Details for the steps are in the full BTG Gitian Build Guide.