I have been working for the different kinds of Node JS application from the last 4 years. For every project I tried to improve the performance and code quality. From that, I found a very interesting way to restart the typescript application so fast. Introduction When you are working with Node JS with Typescript you notice a significant delay while restarting the application by using . ts-node one of the best tool for NodeJS-Typescript development but when comes to typescript it doesn't do the best job. ts-node Typical Typescript NodeJS App A typical nodejs-typescript look like these nodemon.json { : [ ], : , : } "watch" "src" "ext" "ts" "exec" "ts-node ./src/app/server.ts" It will work fine but restart speed is too slow. Don't trust the here, it actually took more than 20 seconds to restart. Server Start time Trail 1 So I was playing with the nodemon options to make restart faster and found we map our executable with params, so I create this configuration for nodemon.json { : { : }, : { : }, : , : [ , ], : , : [ ] } "env" "NODE_ENV" "development" "execMap" "ts" "node --require ts-node/register" "ext" "js,json,ts" "ignore" ".git" "node_modules/**/node_modules" "restartable" "rs" "watch" "src/" This increase the restarting speed, but that not enough for me. So again I started to digging through Google to find better ways. Trail 2 Now I learned to diagnosis typescript and analysis my project by using this command: ./node_modules/.bin/tsc -project ./tsconfig.json --diagnostics This gives an output like these: Files: Lines: Nodes: Identifiers: Symbols: Types: Instantiations: Memory used: K I/O read: s I/O write: s Parse time: s Bind time: s Check time: s Emit time: s Total time: s 372 66423 253384 89381 62938 3327 7640 108724 0.98 0.02 2.20 0.40 0.29 0.16 3.04 I found the command takes only 3 seconds to diagnosis the entire project and the is only taking the time. So started to find an alternatives for the . tsc parse time ts-node Instead of using I tried to restart the application using command. ts-node tsc { : } "dev" "concurrently \"tsc -w\" \"nodemon dist/app/server.js\"" This improves the restarting speed significantly Trail 3 command works great for me, but I still digging google due to curiosity and found a package called tsc ts-node-dev works very different than ts-node. It restarts the target node process only when the files changes and also provide the same file for typescript compilation process between restarts. ts-node-dev This significantly increases the speed of restarting comparing to , etc... nodemon -x ts-node Step 1: Install the package npm i ts-node-dev --save-dev Step 2: Add Configuration { : } "dev" "node_modules/.bin/ts-node-dev --respawn --notify false --prefer-ts --ignore-watch node_modules -- src/app/server.ts " This is the exact configuration I used in my project, this works very fine to me. Step 3: Starts the application npm run dev This will restart the application every time you change a file with blazing speed. Conclusion After testing a lot of tool for developing typescript-nodejs I found the ts-node-dev work like a pro. I recommend to everyone to use the instead of ts-node for your NodeJS-Typescript project. ts-node-dev If you stick this far, thank you so much for reading this article and please consider to follow me on twitter
