diff --git a/app/src/docker/docker-compose.yml b/app/src/docker/docker-compose.yml
index e0ef56fb11..2479c06251 100644
--- a/app/src/docker/docker-compose.yml
+++ b/app/src/docker/docker-compose.yml
@@ -10,6 +10,7 @@ volumes:
 
 # Reusable blocks
 # https://medium.com/@kinghuang/docker-compose-anchors-aliases-extensions-a1e4105d70bd
+# Also note https://yaml.org/type/merge.html
 
 x-common-vars: &common-vars
   # ENV determines which configuration settings to use.
@@ -150,8 +151,7 @@ services:
 
   app:
     image: va/abd_vro-app:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
+    <<: [*common-sde-security, *common-security-opt]
     hostname: app
     ports:
       - "8080:8080"
@@ -159,11 +159,7 @@ services:
     environment:
       # ENV=local causes application-local.yml (and application-nonprod.yml) to be used, in addition to the default application.yml
       # PERSIST_TRACKING_FOLDER is necessary for local testing when ENV=dev or qa
-      <<: *common-vars
-      <<: *rabbitmq-placeholder-vars
-      <<: *redis-placeholder-vars
-      <<: *postgres-vars
-      <<: *mas-vars
+      <<: [*mas-vars, *postgres-vars, *redis-placeholder-vars, *rabbitmq-placeholder-vars, *common-vars]
       PERSIST_TRACKING_FOLDER: /persist/tracking
       BIP_CLAIM_USERID: ${BIP_CLAIM_USERID}
       BIP_CLAIM_SECRET: ${BIP_CLAIM_SECRET}
@@ -192,13 +188,10 @@ services:
 
   xample-workflows:
     image: va/abd_vro-xample-workflows:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
+    <<: [*common-sde-security, *common-security-opt]
     profiles: ["all","xample"]
     environment:
-      <<: *redis-placeholder-vars
-      <<: *rabbitmq-placeholder-vars
-      <<: *postgres-vars
+      <<: [*postgres-vars, *rabbitmq-placeholder-vars, *redis-placeholder-vars]
     depends_on:
       postgres-service:
         condition: service_healthy
@@ -209,12 +202,10 @@ services:
 
   svc-xample-j:
     image: va/abd_vro-svc-xample-j:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
+    <<: [*common-sde-security, *common-security-opt]
     profiles: ["all","svc","xample"]
     environment:
-      <<: *rabbitmq-placeholder-vars
-      <<: *rabbitmq-client-vars
+      <<: [*rabbitmq-client-vars, *rabbitmq-placeholder-vars]
     depends_on:
       rabbitmq-service:
         condition: service_healthy
@@ -224,12 +215,9 @@ services:
   svc-assessor-dc7101:
     profiles: ["all","svc","assessor","v2"]
     image: va/abd_vro-assessclaimdc7101:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
-    <<: *python-healthcheck
+    <<: [*python-healthcheck, *common-sde-security, *common-security-opt]
     environment:
-      <<: *rabbitmq-placeholder-vars
-      <<: *rabbitmq-client-vars
+      <<: [*rabbitmq-client-vars, *rabbitmq-placeholder-vars]
     depends_on:
       rabbitmq-service:
         condition: service_healthy
@@ -239,12 +227,9 @@ services:
   svc-assessor-dc6602:
     profiles: ["all","svc","assessor","v2"]
     image: va/abd_vro-assessclaimdc6602:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
-    <<: *python-healthcheck
+    <<: [*python-healthcheck, *common-sde-security, *common-security-opt]
     environment:
-      <<: *rabbitmq-placeholder-vars
-      <<: *rabbitmq-client-vars
+      <<: [*rabbitmq-client-vars, *rabbitmq-placeholder-vars]
     depends_on:
       rabbitmq-service:
         condition: service_healthy
@@ -254,12 +239,9 @@ services:
   svc-assessor-dc6602v2:
     profiles: ["all","svc","assessor","prototype"]
     image: va/abd_vro-assessclaimdc6602v2:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
-    <<: *python-healthcheck
+    <<: [*python-healthcheck, *common-sde-security, *common-security-opt]
     environment:
-      <<: *rabbitmq-placeholder-vars
-      <<: *rabbitmq-client-vars
+      <<: [*rabbitmq-client-vars, *rabbitmq-placeholder-vars]
     depends_on:
       rabbitmq-service:
         condition: service_healthy
@@ -269,12 +251,9 @@ services:
   svc-assessor-cancer:
     profiles: ["all","svc","assessor","prototype"]
     image: va/abd_vro-assessclaimcancer:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
-    <<: *python-healthcheck
+    <<: [*python-healthcheck, *common-sde-security, *common-security-opt]
     environment:
-      <<: *rabbitmq-placeholder-vars
-      <<: *rabbitmq-client-vars
+      <<: [*rabbitmq-client-vars, *rabbitmq-placeholder-vars]
     depends_on:
       rabbitmq-service:
         condition: service_healthy
@@ -284,12 +263,9 @@ services:
   svc-assessor-dc6510:
     profiles: ["all","svc","assessor","prototype"]
     image: va/abd_vro-assessclaimdc6510:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
-    <<: *python-healthcheck
+    <<: [*python-healthcheck, *common-sde-security, *common-security-opt]
     environment:
-      <<: *rabbitmq-placeholder-vars
-      <<: *rabbitmq-client-vars
+      <<: [*rabbitmq-client-vars, *rabbitmq-placeholder-vars]
     depends_on:
       rabbitmq-service:
         condition: service_healthy
@@ -299,12 +275,9 @@ services:
   svc-assessor-dc6522:
     profiles: ["all","svc","assessor","prototype"]
     image: va/abd_vro-assessclaimdc6522:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
-    <<: *python-healthcheck
+    <<: [*python-healthcheck, *common-sde-security, *common-security-opt]
     environment:
-      <<: *rabbitmq-placeholder-vars
-      <<: *rabbitmq-client-vars
+      <<: [*rabbitmq-client-vars, *rabbitmq-placeholder-vars]
     depends_on:
       rabbitmq-service:
         condition: service_healthy
@@ -314,14 +287,10 @@ services:
   svc-pdf-generator:
     profiles: ["all","svc","pdfgen"]
     image: va/abd_vro-pdfgenerator:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
-    <<: *python-healthcheck
+    <<: [*python-healthcheck, *common-sde-security, *common-security-opt]
     environment:
       MODE: "docker"
-      <<: *redis-placeholder-vars
-      <<: *rabbitmq-placeholder-vars
-      <<: *rabbitmq-client-vars
+      <<: [*rabbitmq-client-vars, *rabbitmq-placeholder-vars, *redis-placeholder-vars]
     depends_on:
       redis-service:
         condition: service_started
@@ -333,12 +302,10 @@ services:
   svc-lighthouse-api:
     profiles: ["all","svc","lh"]
     image: va/abd_vro-service-data-access:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
+    <<: [*common-sde-security, *common-security-opt]
     environment:
       # ENV=local causes application-local.properties to be used, in addition to the default application.properties
-      <<: *common-vars
-      <<: *rabbitmq-placeholder-vars
+      <<: [*rabbitmq-placeholder-vars, *common-vars]
       LH_PRIVATE_KEY: ${LH_PRIVATE_KEY}
       LH_ACCESS_CLIENT_ID: ${LH_ACCESS_CLIENT_ID}
     depends_on:
@@ -350,11 +317,9 @@ services:
   svc-bgs-api:
     profiles: ["all","svc","bgs"]
     image: va/abd_vro-svc-bgs-api:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
+    <<: [*common-sde-security, *common-security-opt]
     environment:
-      <<: *common-vars
-      <<: *rabbitmq-placeholder-vars
+      <<: [*rabbitmq-placeholder-vars, *common-vars]
       # A mock-bgs-api needs to be created and exposes an unused port
       BGS_BASE_URL: http://mock-bgs-api:9020
     depends_on:
@@ -366,12 +331,9 @@ services:
   svc-feature-toggle:
     profiles: ["all","svc","feature-toggle"]
     image: va/abd_vro-featuretoggle:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
+    <<: [*common-sde-security, *common-security-opt]
     environment:
-      <<: *redis-placeholder-vars
-      <<: *rabbitmq-placeholder-vars
-      <<: *rabbitmq-client-vars
+      <<: [*rabbitmq-client-vars, *rabbitmq-placeholder-vars, *redis-placeholder-vars]
     depends_on:
       redis-service:
         condition: service_started
@@ -389,9 +351,7 @@ services:
     stdin_open: true
     tty: true
     environment:
-      <<: *redis-placeholder-vars
-      <<: *rabbitmq-placeholder-vars
-      <<: *postgres-vars
+      <<: [*postgres-vars, *rabbitmq-placeholder-vars, *redis-placeholder-vars]
     depends_on:
       postgres-service:
         condition: service_healthy
@@ -410,8 +370,7 @@ services:
   mock-bip-ce-api:
     profiles: ["all","mock","bip","v2-mocks"]
     image: va/abd_vro-mock-bip-ce-api:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
+    <<: [*common-sde-security, *common-security-opt]
     hostname: mock-bip-ce-api
     ports:
       - "8094:8094"
@@ -431,8 +390,7 @@ services:
   mock-bip-claims-api:
     profiles: ["all","mock","bip","v2-mocks"]
     image: va/abd_vro-mock-bip-claims-api:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
+    <<: [*common-sde-security, *common-security-opt]
     hostname: mock-bip-claims-api
     ports:
       - "8097:8097"
@@ -452,8 +410,7 @@ services:
   mock-mas-api:
     profiles: ["all","mock","mas","v2-mocks"]
     image: va/abd_vro-mock-mas-api:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
+    <<: [*common-sde-security, *common-security-opt]
     hostname: mock-mas-api
     ports:
       - "9001:9001"
@@ -474,8 +431,7 @@ services:
   mock-lighthouse-api:
     profiles: ["all","mock","lh","v2-mocks"]
     image: va/abd_vro-mock-lighthouse-api:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
+    <<: [*common-sde-security, *common-security-opt]
     hostname: mock-lighthouse-api
     environment:
       # ENV=local causes application-local.properties to be used, in addition to the default application.properties
@@ -488,8 +444,7 @@ services:
   mock-slack:
     profiles: ["all","mock","lh","v2-mocks"]
     image: va/abd_vro-mock-slack:latest
-    <<: *common-security-opt
-    <<: *common-sde-security
+    <<: [*common-sde-security, *common-security-opt]
     hostname: mock-slack
     ports:
       - "9008:9008"