Minimum working v0.23 configuration

upstream:
  default:
    - 46.182.19.48
    - 80.241.218.68
    - tcp-tls:fdns1.dismail.de:853
    - https://dns.digitale-gesellschaft.ch/dns-query

blocking:
  blackLists:
    ads:
      - https://raw.githubusercontent.com/StevenBlack/hosts/master/hosts
  clientGroupsBlock:
    default:
      - ads

ports:
  dns: 53
  http: 4000

Upgrading the package fails with the following error message: ~/.cache/yay/blocky-bin/PKGBUILD: line 40: cd: null directory, when using yay. I changed the $src into $srcdir and makepkg succeeded to build it, so that may be a typo?

Minimum working v0.23 configuration

upstream:
  default:
    - 46.182.19.48
    - 80.241.218.68
    - tcp-tls:fdns1.dismail.de:853
    - https://dns.digitale-gesellschaft.ch/dns-query

blocking:
  blackLists:
    ads:
      - https://raw.githubusercontent.com/StevenBlack/hosts/master/hosts
  clientGroupsBlock:
    default:
      - ads

ports:
  dns: 53
  http: 4000

Sample config file for v0.23

ports:
  dns: 127.0.0.1:53,[::1]:53

upstreams:
  groups:
    default:
      - https://security.cloudflare-dns.com/dns-query
      - https://firefox.dns.nextdns.io

blocking:
  blackLists:
    all:
      - https://cdn.jsdelivr.net/gh/hagezi/dns-blocklists@latest/wildcard/ultimate.txt #extreme ads, malware etc from hagezi
#      - https://nsfw.oisd.nl/domainswild #NSFW from oisd
  blockType: nxDomain
  clientGroupsBlock:
    default:
      - all

bootstrapDns:
  - 9.9.9.9
  - 1.0.0.1


# only if you want blocky to read your hosts file
hostsFile:
  sources:
  - /etc/hosts
  loading:
    refreshPeriod: 30m  
    strategy: fast
  hostsTTL: 1h

As commented by jamies there is a bug in the systemd service file for a long time. @x0x01, can you please update the systemd service file?

Also the config in the pinned comment might be a bit outdated.

There's an issue with the service file: /usr/lib/systemd/system/blocky.service

To fix it:

sudo sed -i -e 's/network-online.target/multi-user.target/' /usr/lib/systemd/system/blocky.service
sudo systemctl daemon-reload
sudo systemctl enable blocky --now

Every time I start my computer I have to restart blocky otherwise it won't work. I even double checked if I "enabled" the blocky service.

Edit file /etc/blocky/blocky.yml according to upstream documentation. Then start & enable blocky.service.

For example, this is how my /etc/blocky/blocky.yml file looks like:

upstream:
    externalResolvers:
      - https://security.cloudflare-dns.com/dns-query

blocking:
    # definition of blacklist groups. Can be external link (http/https) or local file
    blackLists:
      blocklists:
        - http://sysctl.org/cameleon/hosts
        - https://dbl.oisd.nl/
        - https://mirror1.malwaredomains.com/files/justdomains
        - https://raw.githubusercontent.com/crazy-max/WindowsSpyBlocker/master/data/hosts/spy.txt
        - https://raw.githubusercontent.com/erkexzcx/disconnectme-pihole/master/services_Advertising.txt
        - https://raw.githubusercontent.com/erkexzcx/disconnectme-pihole/master/services_Analytics.txt
        - https://raw.githubusercontent.com/erkexzcx/disconnectme-pihole/master/services_Cryptomining.txt
        - https://raw.githubusercontent.com/erkexzcx/disconnectme-pihole/master/services_FingerprintingInvasive.txt
        - https://s3.amazonaws.com/lists.disconnect.me/simple_ad.txt
        - https://s3.amazonaws.com/lists.disconnect.me/simple_tracking.txt
        - https://zeustracker.abuse.ch/blocklist.php?download=domainblocklist
        - https://raw.githubusercontent.com/StevenBlack/hosts/master/hosts
        - http://sysctl.org/cameleon/hosts
    clientGroupsBlock:
      default:
        - blocklists
    blockType: zeroIp
    refreshPeriod: 0

bootstrapDns: tcp:1.1.1.1

logLevel: error