oh well it isn't supported

.devcontainer/Dockerfile

@@ -1 +0,0 @@
-FROM mcr.microsoft.com/vscode/devcontainers/javascript-node:12

.devcontainer/devcontainer.json

@@ -1,17 +0,0 @@
-{
-    "name": "Writer app",
-    "dockerFile": "Dockerfile",
-    // Use 'appPort' to create a container with published ports. If the port isn't working, be sure
-    // your server accepts connections from all interfaces (0.0.0.0 or '*'), not just localhost.
-    "appPort": [
-        1234,
-        3000
-    ],
-    // Use 'settings' to set *default* container specific settings.json values on container create. 
-    // You can edit these settings after create using File > Preferences > Settings > Remote.
-    "settings": {
-        "terminal.integrated.shell.linux": "/bin/zsh"
-    },
-    // Specifies a command that should be run after the container has been created.
-    //"postCreateCommand": "npm i && cd frontend && npm i",
-}

.devcontainer/docker-compose.yml

@@ -1,35 +0,0 @@
-#-------------------------------------------------------------------------------------------------------------
-# Copyright (c) Microsoft Corporation. All rights reserved.
-# Licensed under the MIT License. See https://go.microsoft.com/fwlink/?linkid=2090316 for license information.
-#-------------------------------------------------------------------------------------------------------------
-
-version: '3'
-services:
-  app:
-    # Uncomment the next line to use a non-root user for all processes. You can also
-    # simply use the "remoteUser" property in devcontainer.json if you just want VS Code
-    # and its sub-processes (terminals, tasks, debugging) to execute as the user. On Linux,
-    # you may need to update USER_UID and USER_GID in .devcontainer/Dockerfile to match your
-    # user if not 1000. See https://aka.ms/vscode-remote/containers/non-root for details.
-    # user: node
-
-    build: 
-      context: .
-      dockerfile: Dockerfile
-          
-    # Overrides default command so things don't shut down after the process ends.
-    command: sleep infinity
-
-    links:
-      - db
-
-  db:
-    image: mariadb
-    restart: unless-stopped
-    ports: 
-      - 3306:3306
-    environment:
-      MYSQL_PASSWORD: writer
-      MYSQL_USER: writer
-      MYSQL_DATABASE: writer
-      MYSQL_ROOT_PASSWORD: writerroot