{
  "$schema": "./node_modules/@angular/cli/lib/config/schema.json",
  "version": 1,
  "projects": {
    "ng-http-loader": {
      "root": "",
      "sourceRoot": "src",
      "projectType": "library",
      "schematics": {
        "@schematics/angular:component": {
          "styleext": "scss"
        }
      },
      "architect": {
        "build": {
          "builder": "@angular-devkit/build-ng-packagr:build",
          "options": {
            "tsConfig": "./tsconfig.lib.json",
            "project": "./ng-package.json"
          }
        },
        "test": {
          "builder": "@angular-devkit/build-angular:karma",
          "options": {
            "main": "./src/test.ts",
            "karmaConfig": "./karma.conf.js",
            "polyfills": "./polyfills.ts",
            "tsConfig": "./tsconfig.spec.json",
            "watch": false,
            "sourceMap": true
          }
        },
        "lint": {
          "builder": "@angular-devkit/build-angular:tslint",
          "options": {
            "tsConfig": [
              "./tsconfig.lib.json",
              "./tsconfig.spec.json"
            ],
            "exclude": [
              "**/node_modules/**"
            ]
          }
        }
      }
    }
  },
  "defaultProject": "ng-http-loader"
}

{
  "$schema": "./node_modules/@angular/cli/lib/config/schema.json",
  "version": 1,
  "projects": {
    "ng-http-loader": {
      "root": "",
      "sourceRoot": "src",
      "projectType": "library",
      "schematics": {
        "@schematics/angular:component": {
          "styleext": "scss"
        }
      },
      "architect": {
        "build": {
          "builder": "@angular-devkit/build-ng-packagr:build",
          "options": {
            "tsConfig": "./tsconfig.lib.json",
            "project": "./ng-package.json"
          }
        },
        "test": {
          "builder": "@angular-devkit/build-angular:karma",
          "options": {
            "main": "./src/test.ts",
            "karmaConfig": "./karma.conf.js",
            "polyfills": "./polyfills.ts",
            "tsConfig": "./tsconfig.spec.json",
            "watch": false,
            "sourceMap": true
          }
        },
        "lint": {
          "builder": "@angular-devkit/build-angular:tslint",
          "options": {
            "tsConfig": [
              "./tsconfig.lib.json",
              "./tsconfig.spec.json"
            ],
            "exclude": [
              "**/node_modules/**"
            ]
          }
        }
      }
    }
  },
  "defaultProject": "ng-http-loader",
  "cli": {
    "packageManager": "yarn"
  }
}

Add packageManager section and force it to 'yarn'
Add packageManager section and force it to 'yarn'
