• Webpack config is a TS file, not JS.
• [email protected]
• typescript 3.8.3
• [email protected]
• workaround: enabling skipLibCheck TS compilation flag (not for the entire code base but just for the code part that compiles/runs webpack using the config presented in TS code).

ERROR in node_modules/ts-loader/dist/interfaces.d.ts:57:18 - error TS2320: Interface 'SolutionBuilderWithWatchHost' cannot simultaneously extend types 'SolutionBuilderWithWatchHost' and 'WatchFactory'.
Named property 'watchDirectory' of types 'SolutionBuilderWithWatchHost' and 'WatchFactory' are not identical.

57 export interface SolutionBuilderWithWatchHost extends typescript.SolutionBuilderWithWatchHost<typescript.EmitAndSemanticDiagnosticsBuilderProgram>, WatchFactory {
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
node_modules/ts-loader/dist/interfaces.d.ts:57:18 - error TS2320: Interface 'SolutionBuilderWithWatchHost' cannot simultaneously extend types 'SolutionBuilderWithWatchHost' and 'WatchFactory'.
Named property 'watchFile' of types 'SolutionBuilderWithWatchHost' and 'WatchFactory' are not identical.

57 export interface SolutionBuilderWithWatchHost extends typescript.SolutionBuilderWithWatchHost<typescript.EmitAndSemanticDiagnosticsBuilderProgram>, WatchFactory {