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var sandboxDebugger = require("sandbox-debugger")

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sandbox-debugger v0.2.39

sandbox debugger client for node


js-standard-style build status Docker Image CI downloads Docker Pulls

Debug a Node.js process anywhere using chrome://inspect or node-inspect

node debug port 9229sandbox debug clientsandbox debug broker

Interactive debugging using inspect, debug the same way you do with a local process.

Supports a Node.js process running

How it works?

Node opens a websocket when in debug mode, both the sandbox server and client work by piping the websocket data via the broker.

Run sandbox server

The server is used as a gatekeeper for the debug messages.

npx sandbox-debugger-server


ᐅ docker run \
  --name sandbox-debugger \
  -ti \
  --rm \
  -p 9229:9229 \

The server will output

   Debug server started!                       
    - To debug a new process:                  
      node index.js                            
    - To debug an existing process:            
      export DEBUG_PID=<pid of node process>   
      npx sandbox-debugger                     

    - Find pid of first running Node.js process
      ps ax |
      grep 'no[d]e ' |
      awk '{print $1}' |
      head -n 1
    - Allow remote access to me:              
      npx ngrok http 9229                      

Create a tunnel to our sandbox server process

Using ngrok you can tunnel to the locally running broker from for example aws lambda.

npx ngrok http 9229


Example debug current process

// index.js
console.log('all done')

# DEBUG_PROXY is ip:port to sandbox broker
DEBUG_PROXY=ip:port node index.js

Example debug an already running process

# DEBUG_PROXY is ip:port to sandbox broker
# DEBUG_PID is pid of process to debug
DEBUG_PROXY=ip:port DEBUG_PID=x npx sandbox-debugger

AWS Lambda

Environment variable DEBUG_PROXY needs to point to the ngrok address including the port part :80.

The easiest way to debug lambda is to edit the code in aws console.

  • Copy the contents of to debug.js
  • require('./debug.js') instead of sandbox-debugger


Use a lambda layer containing the sandbox-debugger, you can publish your own for node 12 here and also node 10 here.


Apache License, Version 2.0


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