Here are a few more details of my setup:

Components:

• server
• clients (phone/laptop)
• domain name (we'll call it custom.domain)
• home router
• dynamic DNS provider

The home router has WireGuard port forwarded to server, with no re-mapping (I'm using the default 51820). It's also providing DHCP services to my home network, using the 192.168.1.0/24 network.

The server is running the dynamic DNS client (keeping the dynamic domain name updated to my public IP), and I have a CNAME record on the vpn.custom.domain pointing to the dynamic DNS name (which is an awful random string of characters). I also have server.custom.domain with an A record pointing to 10.30.0.1. All my DNS records are in public DNS (so no need to change the DNS settings on the computer or phone or use DNS overrides with WireGuard.)

Immich config:

version: "3.8"

services:
  immich-server:
    container_name: immich_server
    image: ghcr.io/immich-app/immich-server:release
    entrypoint: ["/bin/sh", "./start-server.sh"]
    volumes:
      - ${UPLOAD_LOCATION}:/usr/src/app/upload
    env_file:
      - .env
    ports:
      - target: 3001
        published: 2283
        host_ip: 10.30.0.1
    depends_on:
      - redis
      - database
    restart: always
    networks:
      - immich

WireGuard is configured using wg-quick (/etc/wireguard/wg0.conf):

[Interface]
Address = 10.30.0.1/16
PrivateKey = <server-private-key>
ListenPort = 51820

[Peer]
PublicKey = <phone-public-key>
AllowedIPs = 10.30.0.12/32

[Peer]
PublicKey = <laptop-public-key>
AllowedIPs = 10.30.0.11/32

Start WireGuard with systemctl enable --now wg-quick@wg0.

Phone WireGuard configuration (iOS):

[Interface]
Name = vpn.custom.domain

Private Key = <phone private key>
Public Key = <phone public key>

Addresses = 10.30.0.12/32
Listen port = <blank>
MTU = <blank>
DNS servers = <blank>

[Peer]
Public Key = <server public key>
Pre-shared key = <blank>
Endpoint = vpn.custom.domain:51820
Allowed IPs = 10.30.0.0/16
Persistent Keepalive = 25

[On Demand Activation]
Cellular = On
Wi-Fi = On
SSIDs = Any SSID

This connection is then left always enabled, and comes on whenever my phone has any kind of network connection.

My laptop (running Linux), is also using wg-quick (/etc/wireguard/wg0.conf):

[Interface]
Address = 10.30.0.14
PrivateKey = <laptop private key>

[Peer]
PublicKey = <server-public-key>
Endpoint = vpn.custom.domain:51820
AllowedIPs = 10.30.0.0/16

My wife's window's laptop is configured using the official WireGuard windows app, with similar settings.

No matter where we are (at home, on a WiFi hotspot, or using cellular data) we access Immich over the VPN: http://server.custom.comain:2283/.

Let me know if you have any further questions.