tsconfig options that matter

A short list of options with large consequences

target decides which syntax is downlevelled, module decides what the emitted imports look like, and module resolution decides how specifiers are found on disk. Mismatching them against your runtime produces confusing failures that look like bugs in your code.

In most modern setups a bundler does the emitting and the compiler only checks types. Saying so explicitly avoids two tools disagreeing about the output.

Everything else is preference until it is not. Skipping library checks speeds up builds and hides genuine incompatibilities between dependency type versions.