diff --git a/.env.example b/.env.example
new file mode 100644
index 0000000..c0c68b1
--- /dev/null
+++ b/.env.example
@@ -0,0 +1 @@
+PORT=3000
\ No newline at end of file
diff --git a/.gitignore b/.gitignore
index 090a5b6..1e2ef7f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 node_modules
 src/dist
-dev/docker/stacks/main/assets
\ No newline at end of file
+dev/docker/stacks/main/assets
+.env
\ No newline at end of file
diff --git a/dev/docker/images/main/Dockerfile b/dev/docker/images/main/Dockerfile
index 9a9e48d..8a887de 100644
--- a/dev/docker/images/main/Dockerfile
+++ b/dev/docker/images/main/Dockerfile
@@ -4,10 +4,9 @@ WORKDIR /app
 COPY src/ ./src
 COPY package.json ./
 COPY yarn.lock ./
+COPY .env.example ./.env
 COPY assets /assets
 COPY dev/shell/entrypoint.sh /entrypoint.sh
-RUN yarn
-RUN yarn clean
-RUN yarn build-prod
+RUN yarn && yarn clean && yarn build-prod
 EXPOSE 3000
 ENTRYPOINT ["/bin/sh", "/entrypoint.sh"]
\ No newline at end of file
diff --git a/dev/docker/stacks/main/compose.yml b/dev/docker/stacks/main/compose.yml
index c0ba82f..9997809 100644
--- a/dev/docker/stacks/main/compose.yml
+++ b/dev/docker/stacks/main/compose.yml
@@ -1,9 +1,11 @@
 version: '3'
 services:
   app:
-    image: nikurasukun/socialtree
+    image: git.oishi-ra.men/nikurasu/socialtree-js:latest
     container_name: socialtree
+    environment:
+      PORT: 3000
     volumes:
       - ./assets:/app/assets/
     ports:
-      - 80:3000
\ No newline at end of file
+      - 3000:3000
\ No newline at end of file
diff --git a/dev/shell/docker-prod.sh b/dev/shell/docker-prod.sh
index 26358d2..12f4a58 100755
--- a/dev/shell/docker-prod.sh
+++ b/dev/shell/docker-prod.sh
@@ -1 +1 @@
-docker build -t git.oishi-ra.men/nikurasu/socialtree-js -f dev/docker/images/main/Dockerfile --no-cache .
\ No newline at end of file
+docker build -t git.oishi-ra.men/nikurasu/socialtree-js:latest -f dev/docker/images/main/Dockerfile --no-cache .
\ No newline at end of file
diff --git a/package.json b/package.json
index 005d742..1913923 100644
--- a/package.json
+++ b/package.json
@@ -15,6 +15,7 @@
     "build-prod": "sass --style=compressed src/public/themes:src/dist/style"
   },
   "dependencies": {
+    "dotenv": "^16.0.3",
     "ejs": "^3.1.8",
     "express": "^4.18.2",
     "js-yaml": "^4.1.0"
diff --git a/src/index.js b/src/index.js
index 91325ef..55d4835 100644
--- a/src/index.js
+++ b/src/index.js
@@ -1,11 +1,13 @@
 import express from 'express'
 import yaml from 'js-yaml'
 import fs from 'node:fs'
+import * as dotenv from 'dotenv'
 
 console.log('🔧 Configuring socialtree...')
 
+dotenv.config()
 const app = express()
-const port = 3000
+const port = process.env.PORT
 const engine = 'ejs'
 
 app.set('view engine', engine)
diff --git a/yarn.lock b/yarn.lock
index 43f696b..4b1b842 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -211,6 +211,11 @@ destroy@1.2.0:
   resolved "https://registry.yarnpkg.com/destroy/-/destroy-1.2.0.tgz#4803735509ad8be552934c67df614f94e66fa015"
   integrity sha512-2sJGJTaXIIaR1w4iJSNoN0hnMY7Gpc/n8D4qSCJw8QqFWXf7cuAgnEHxBpweaVcPevC2l3KpjYCx3NypQQgaJg==
 
+dotenv@^16.0.3:
+  version "16.0.3"
+  resolved "https://registry.yarnpkg.com/dotenv/-/dotenv-16.0.3.tgz#115aec42bac5053db3c456db30cc243a5a836a07"
+  integrity sha512-7GO6HghkA5fYG9TYnNxi14/7K9f5occMlp3zXAuSxn7CKCxt9xbNWG7yF8hTCSUchlfWSe3uLmlPfigevRItzQ==
+
 ee-first@1.1.1:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/ee-first/-/ee-first-1.1.1.tgz#590c61156b0ae2f4f0255732a158b266bc56b21d"