Thunder Client — lightweight alternative to Postman

Extension Design Goals

  • Lightweight API Client
  • Simple, Clean & Easy to use UI
  • Handle Large Responses & View in Full Screen
  • Support VS Code Themes
  • Collections & Environment Variables
  • Scriptless Testing


I started initial research on how to use VS Code api to develop an extension for couple of days and then started developing the software. Finally able to complete the development of Extension with the above target functionality. below is the screenshot of the extension

Thunder Client Extension


The tech used to develop the VS Code extension are Javascript, Flexbox, Typescript, Ace Editor, Got, Nedb. No javascript or bootstrap frameworks used.

Scriptless Testing

I noticed we need to write lot of boilerplate code in Postman and other clients to do basic testing using scripting like status code equal 200. So I implemented GUI based tests, where you can select couple of dropdowns to do most standard tests very easily without any scripting knowledge. Below is the screenshot of tests.

Thunder Client Testing
// status code test
pm.test("Status code is 200", function () {;});// property check
pm.test("Property message contains Thunder Client", function () {
var jsonData = pm.response.json(); pm.expect(jsonData.message).to.contains("Thunder Client");});// response content-type check
pm.test("Content-Type contains application/json", function () {"Content-Type", "application/json");});

Extension Links


Please download the extension and let me know what you like or any feedback. To report any bugs or feature requests visit the github support page.


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