tsconfig.json with comments and explanations

tsconfig-all.js

{
  // Config for IDE to reload
  "compileOnSave": true,
  "exclude": [
    // Specifies an array of filenames or patterns that should be skipped when resolving include.
    // Default:
    // ["node_modules", "bower_components", "jspm_packages"], plus the value of outDir if one is specified.
    "**/*.spec.ts",
    "node_modules"
  ],
  "include": [
    // Specifies an array of filenames or patterns to include in the program.
    // Usually this config is empty.
    // Default:
    // [] if files are specified, otherwise ["**/*"]
  ],
  // The value of extends is a string which contains a path to another configuration file to inherit from. The path may use Node.js style resolution.
  "extends": "../tsconfig-base.json",
  "files": [
    // Specifies an allowlist of files to include in the program.
    // If empty takes all files
    // Default:
    // false
    "core.ts",
    "sys.ts"
  ],
  "references": [
    // Helps to organize applications splitted in smaller modules
    // https://stackoverflow.com/questions/51631786/how-to-use-project-references-in-typescript-3-0
    { "path": "../src" }
  ],
  "typeAcquisition": {
    // Provides default typings from DefinitelyTyped library for js libraries in node_modules
    // Create jsconfig.json in the root of your project with some of next configs if you want to customize it.
    "include": ["jest"],
    "exclude": ["jquery"]
  },
  "compilerOptions": {
    /* Most important and used TS compiler options */
    "allowJs": false, // allow to import js files in your projects, usefull when you import js libs in your project
    "allowUmdGlobalAccess": false, // Allolw UMD exports as global, when they are not available in runtime
    "baseUrl": "./src", // base directory to resolve all module and file names from
    "emitDecoratorMetadata": true, // support for types in metadata for decorators, Angular important
    "experimentalDecorators": true, // support for types in decorators, Angular important
    "importHelpers": false, // imports some operations from "tslib", instead of creation them in each file where are they used
    "module": "CommonJS", // JS module system, values: "ES2020" | "None" | "UMD" | "AMD" | "System" | "ESNext", list with examples: https://www.typescriptlang.org/tsconfig#module
    "moduleResolution": "node", // module resolution strategy, 'node' | 'classic', classic is for TS < 1.6
    "noEmit": false, // do not create JS output files
    "outDir": "n/a", // where put transpiled JS files, without value  puts in same folder with TS files
    "outFile": "n/a", // bundle file with all concatenated JS files
    "plugins": [], // plugins for IDE to parse your code better
    "resolveJsonModule": false, // include json files by default in your project as a module
    "sourceMap": false, // enables generation of source maps - files allow debuggers and other tools to analyze your code
    "target": "es3", // which EcmaScript version should tsc follow when transpiles your files, if no limitations prefer to use latest versions, values: es3, es5, es6 ,esnext, es2020
    "types": ["node", "jest", "express"], // if specified, includes only listed lists of types
    "typeRoots": [
      // All @types packages are usually visible for your project, specify which types to include
      "node_modules/@types"
    ],
    "lib": [
      // List of imported libraries required for your project, full list: https://github.com/microsoft/TypeScript/tree/main/src/lib
      // You can specify them for your platform (browser/not a browser), EcmaScript Versions and etc
      "es2018",
      "es6"
    ],
    "paths": {
      // Map of urls for easier imports
      "modules/*": ["app/modules/*"],
      "environment/*": ["environments/*"]
    },
    /* End Most important and used TS compiler options */

    /* Build options - options mainly for build stage to change behaviour of project compilation */
    "declaration": false, // generate declaration file.d.ts files after transpilation TS -> JS
    "declarationMap": false, // generate source-map files so IDE can work with original TS file
    "declarationDir": "n/a", // configure root directory for declaration files
    "emitDeclarationOnly": false, // emit d.ts files for a js file, do not emit JS files
    "inlineSourceMap": false, // instead of .js.map with js file, puts .js.map content into .js file
    "inlineSources": false, // put .ts sources inside with compiled js, requires sourceMap or inlineSourceMap
    "mapRoot": ".", // path for debugger with sourcemaps
    "sourceRoot": "https://my-website.com/debug/source/", // path for debugger with source code

    "downlevelIteration": false, // transpilation TS -> JS generates older JS versions
    "emitBOM": false, // flag to write UTF-8 Byte Order Mark
    "isolatedModules": false, // helps to resolve imports for single file builders like Babel
    "newLine": "CRLF", // End of line type in bundle files
    "noEmitHelpers": false, // do not put helpers in result bundle files
    "noEmitOnError": false, // do not create build results, if any errors were reported. Helps in dev-watch mode
    "noImplicitUseStrict": false, // disable default 'use strict' in every file
    "noLib": false, // do not include libs and provide your own types
    "noResolve": false, // do not add "/// <reference path="..." />" in bundle results files
    "preserveConstEnums": false, // do not transpile const enum to values and include in result code them, browser compatibility
    "removeComments": false, // removes comments from your TS codebase when TS -> JS
    /* End Build Options */

    /* Codestyles - how to make your TS code more static typed and improve its quality */
    "alwaysStrict": false, // 'use strict' for all files, recommend to turn on
    // Start strict typechecks
    "strict": false, // turn on next flags, recommend to turn it on for better code quality:
    "noImplicitAny": false, // error when no type provided
    "noImplicitThis": false, // keep 'this' pointed to the class or with provided type
    "strictBindCallApply": false, // typecheck for bind, call and apply methods
    "strictFunctionTypes": false, // typecheck for function parameters mor rigorous
    "strictNullChecks": false, // typecheck for null and undefined to avoid bugs
    "strictPropertyInitialization": false, // strict check for value initialization of the class property
    // End strict typechecks
    "noFallthroughCasesInSwitch": false, // check switch for break and return
    "noImplicitReturns": false, // check if all code parts return value
    "noPropertyAccessFromIndexSignature": false, // provide consistency for obj.key & obj["key"], since 4.2
    "noUncheckedIndexedAccess": false, // add undefined to unknown properties defined in [propName: string]: string;, since 4.1
    "noUnusedLocals": false, // report errors on not used variables
    "noUnusedParameters": false, // report errors on not used function params
    "noStrictGenericChecks": false, // typcheck for generics
    "allowUnreachableCode": undefined, // report unreachable code, undefined - editor, true - allow, false - raise error
    "allowUnusedLabels": false, // do not allow to write labels in JS
    "forceConsistentCasingInFileNames": false, // returns error, when program is trying to load file in wrong case (upper or lower for example)
    /* End Codestyles */

    /* Compiler options - less popular */
    "checkJs": false, // works together with allowJS, if enabled reports JS code errors
    "assumeChangesOnlyAffectDirectDependencies": false, // check only changed files, not the entire project if true
    "disableSizeLimit": false, // disable size limit for project
    "importsNotUsedAsValues": "remove", // save or delete imports used for types only, values: 'remove' | 'preserve' | 'error'
    "maxNodeModuleJsDepth": 0, // The maximum dependency depth to search under node_modules and load JavaScript files, with allowJs
    "skipLibCheck": false, // skip typecheck for declaration files
    "allowSyntheticDefaultImports": false, // allow imports from modules without default exports
    "esModuleInterop": false, // recommended: true, create helpers (__importDefault and etc) to parse CommonJS/AMD/UMD modules correct and follow specs, enables allowSyntheticDefaultImports
    "preserveSymlinks": false, // same with NodeJS and Webpack, resolves relative to the location of the symbolic link file
    "useDefineForClassFields": false, // TODO
    "suppressExcessPropertyErrors": false, // disable excess property error in classes
    "suppressImplicitAnyIndexErrors": false, // turn off any checks for objects indexed like this: obj["foo"]
    /* End Compiler options - less popular */

    /* React TS Configs */
    "jsx": undefined, // controls how to transpile TSX -> JS: "react" | "react-jsx" | "react-jsxdev" | "preserve" | "react-native"
    "jsxFactory": "React.createElement", // factory function to use when compiling TSX functions, possible vallues: 'h' | 'preact.h'
    "jsxFragmentFactory": undefined, // Specify the JSX fragment factory function to use when targeting react JSX emit with jsxFactory compiler option is specified, since 4.0
    "jsxImportSource": "react", // module to use when declare jsx/tsx , since 4.1
    /* End React TS Configs */

    /* Verbose build process */
    "explainFiles": false, // verbose files transpilation, explain files transpilation, since 4.2
    "extendedDiagnostics": false, // verbose files transpilation, show wasted time
    "generateCpuProfile": "profile.cpuprofile", // verbose files transpilation, analyze CPU
    "listEmittedFiles": false, // verbose files transpilation, list filenames transpiled
    "listFiles": false, // verbose files transpilation, print names of files part of the compilation
    "traceResolution": false, // verbose files transpilation, track why module is not included in final bundle
    /* End Verbose build process */

    /* Library configs - these configs can be helpful in big projects or libraries */
    "composite": true, // used together with references from root settings, if you provide ref, ref module must turn on composite
    "incremental": true, // if composite is on, then false; creates .tsbuildinfo file with info about last project compilation
    "tsBuildInfoFile": ".tsbuildinfo", // stores information about TS compilation, as a part of composite projects
    "disableReferencedProjectLoad": false, // should TS load the entire projects in memory or not, since 4.0
    "disableSolutionSearching": false, // composite projects, IDE integration to avoid find all references in the project
    "disableSourceOfProjectReferenceRedirect": false, // composite projects, use .d.ts files for boundaries between modules
    "rootDir": "../src", // does not affect which files become part of the compilation, path to the folder where should TSC start looking for your files
    "rootDirs": ["src/views", "generated/templates/views"], // runtime, to create virtual tree of directories, usefull for libraries
    /* End Library configs */
  },
  // Angular TS configs: https://angular.io/guide/angular-compiler-options
  "angularCompilerOptions": {
    "strictInjectionParameters": false, // generate all possible files even if they are empty
    "annotationsAs": , // TODO
    "annotateForClosureCompiler": false, // Tsickle to annotate JS for Closure Compiler
    "disableExpressionLowering": true, // allow code from annotations to be imported from modules
    "disableTypeScriptVersionCheck": false, // doesn't report if wrong TS version is used
    "enableI18nLegacyMessageIdFormat": true, // use old algorithm of ids for i18n translations
    "enableIvy": true, // true since NG9
    "enableResourceInlining": false, // replaces replaces the templateUrl and styleUrls property in all @Component decorators with inlined contents in template and styles properties
    "enableLegacyTemplate": false, // enables use of the <template> element instead of <ng-template>
    "flatModuleOutFile": "libname.js", // to create flat modules packaged similarly to @angular/core, package.json for the library should refer to the generated flat module index instead of the library index file
    "flatModuleId": "libname", // id to use for the module above
    "generateCodeForLibraries": true, // generates factories for .d.ts files
    "preserveWhitespaces": false, // removes blank text nodes from compiled templates
    "skipMetadataEmit": false, // turn off producing .metadata.json, which contains info for template compiler
    "skipTemplateCodegen": false, // does not emit .ngfactory.js and .ngstyle.js files
    "strictMetadataEmit": false, // check errors in .metadata.json
    /* Codestyle */
    "fullTemplateTypeCheck": false, // provides template typechecking
    "strictInjectionParameters": false, // typecheck for injections
    "strictTemplates": false, // typecheck for template
    "strictInputAccessModifiers": false, // typecheck for input modifiers
  }
}