1 files changed, 28 insertions, 3 deletions
diff --git a/app/drone-ci/integration/docker-compose.yml b/app/drone-ci/integration/docker-compose.yml
index 2644918..57fdd09 100644
--- a/app/drone-ci/integration/docker-compose.yml
+++ b/app/drone-ci/integration/docker-compose.yml
@@ -1,5 +1,14 @@
 version: '3.4'
 services:
+  nix-daemon:
+    image: nixpkgs/nix:nixos-22.05
+    restart: always
+    command: nix-daemon
+    privileged: true
+    volumes:
+      - "nix:/nix"
+      - "./nix.conf:/etc/nix/nix.conf:ro"
+
   drone-runner:
     image: drone/drone-runner-docker:latest
     restart: always
@@ -7,18 +16,32 @@ services:
       - DRONE_RPC_PROTO=https
       - DRONE_RPC_HOST=drone.deuxfleurs.fr
       - DRONE_RPC_SECRET=${DRONE_SECRET}
-      - DRONE_RUNNER_CAPACITY=1
+      - DRONE_RUNNER_CAPACITY=3
       - DRONE_DEBUG=true
       - DRONE_LOGS_TRACE=true
       - DRONE_RPC_DUMP_HTTP=true
       - DRONE_RPC_DUMP_HTTP_BODY=true
-      - DRONE_RUNNER_NAME=${DRONE_NAME}
+      - DRONE_RUNNER_NAME=i_forgot_to_change_my_runner_name
+      - DRONE_RUNNER_LABELS=nix-daemon:1
+      # we should put "nix:/nix:ro but it is not supported by
+      # drone-runner-docker because the dependency envconfig does
+      # not support having two colons (:) in the same stanza.
+      # Without the RO flag (or using docker userns), build isolation
+      # is broken.
+      # https://discourse.drone.io/t/allow-mounting-a-host-volume-as-read-only/10071
+      # https://github.com/kelseyhightower/envconfig/pull/153
+      #
+      # A workaround for isolation is to configure docker with a userns,
+      # so even if the folder is writable to root, it is not to any non
+      # privileged docker daemon ran by drone!
+      - DRONE_RUNNER_VOLUMES=drone_nix:/nix
+      - DRONE_RUNNER_ENVIRON=NIX_REMOTE:daemon
     ports:
       - "3000:3000/tcp"
     volumes:
       - "/var/run/docker.sock:/var/run/docker.sock"
 
-  drone-gc: 
+  drone-gc:
     image: drone/gc:latest
     restart: always
     environment:
@@ -27,3 +50,5 @@ services:
       - GC_INTERVAL=10m
     volumes:
       - "/var/run/docker.sock:/var/run/docker.sock"
+volumes:
+  nix: