datadog-agent v7 is available (https://github.com/DataDog/datadog-agent) and uses python3 by default. There are many new integrations (https://github.com/DataDog/integrations-core) which are incompatible with v6.
The build process seems to have changed, the upgrade steps (https://github.com/NixOS/nixpkgs/blob/master/pkgs/tools/networking/dd-agent/README.md) do not work because there is no Gopkg.lock in the datadog-agent repository. As someone who does not know Go I do not know how to proceed.

Checklist

• Checked the nixpkgs master branch

• Checked the nixpkgs pull requests

Project name

nix search name: datadog-agent

current version: 6.11.2
desired version: 7.24

Notify maintainers

maintainers: @thoughtpolice @domenkozar @rvl

Note for maintainers

Please tag this issue in your PR.