DX - Strict

Layer strict TypeScript checks on top of the essentials baseline so type errors, unused code, and unsafe patterns are caught at compile time.

Why Use This Preset?

Turns on strict and every individual strict flag so the compiler enforces null safety, typed this, and sound function types.
Flags unused locals, parameters, unreachable code, and unused labels so dead code never ships.
Enforces exactOptionalPropertyTypes and noUncheckedIndexedAccess so optional and indexed values are handled explicitly.
Sets isolatedModules and noEmitOnError so files stay safe to transpile per-file and a failed check never emits output.
Overrides the baseline skipLibCheck to false so your dependencies' type declarations are checked too.

Usage

This preset is an overlay and must come after DX - Essentials in the extends chain, then before any environment layer.

tsconfig.json

json

{
  "extends": [
    "@cbnventures/nova/presets/tsconfig/dx-essentials.json",
    "@cbnventures/nova/presets/tsconfig/dx-strict.json",
    "@cbnventures/nova/presets/tsconfig/runtime-node.json"
  ]
}

warning

Using dx-strict on its own yields an incomplete config. It is an overlay that depends on dx-essentials being extended first.

What This Preset Configures

The preset sets the following compilerOptions on top of the essentials baseline.

Setting	Value	Description
`allowArbitraryExtensions`	`false`	Blocks importing files with non-standard extensions as modules.
`allowSyntheticDefaultImports`	`true`	Keeps default imports from no-default modules working under `skipLibCheck: false`.
`allowUnreachableCode`	`false`	Reports code that can never run.
`allowUnusedLabels`	`false`	Reports labels that are never referenced.
`alwaysStrict`	`true`	Parses every file in strict mode and emits `"use strict"`.
`exactOptionalPropertyTypes`	`true`	Distinguishes a missing optional property from one set to `undefined`.
`forceConsistentCasingInFileNames`	`true`	Rejects imports whose path casing does not match the file on disk.
`isolatedModules`	`true`	Ensures each file can be safely transpiled on its own.
`noEmitOnError`	`true`	Suppresses all output when the build reports a type error.
`noFallthroughCasesInSwitch`	`true`	Reports a `switch` case that falls through without `break` or `return`.
`noImplicitAny`	`true`	Reports values whose type is silently inferred as `any`.
`noImplicitOverride`	`true`	Requires the `override` keyword when a method overrides a base member.
`noImplicitReturns`	`true`	Reports code paths in a function that do not return a value.
`noImplicitThis`	`true`	Reports `this` with an implicit `any` type.
`noImplicitUseStrict`	`false`	Leaves the standard `"use strict"` emit in place.
`noPropertyAccessFromIndexSignature`	`true`	Requires bracket access for properties that come from an index signature.
`noUncheckedIndexedAccess`	`true`	Adds `undefined` to the type of indexed access results.
`noUncheckedSideEffectImports`	`true`	Reports side-effect imports that resolve to nothing.
`noUnusedLocals`	`true`	Reports declared local variables that are never read.
`noUnusedParameters`	`true`	Reports function parameters that are never read.
`skipLibCheck`	`false`	Type-checks declaration files, overriding the essentials baseline.
`strict`	`true`	Enables the full strict family of type-checking options.
`strictBindCallApply`	`true`	Type-checks the arguments to `bind`, `call`, and `apply`.
`strictBuiltinIteratorReturn`	`true`	Types built-in iterator return values precisely.
`strictFunctionTypes`	`true`	Checks function parameters contravariantly for sound assignability.
`strictNullChecks`	`true`	Treats `null` and `undefined` as distinct, non-assignable types.
`strictPropertyInitialization`	`true`	Requires class properties to be assigned in the constructor.
`useDefineForClassFields`	`true`	Emits class fields using the standard `define` semantics.
`useUnknownInCatchVariables`	`true`	Types `catch` clause variables as `unknown` instead of `any`.

info

allowSyntheticDefaultImports is kept true here on purpose. With skipLibCheck: false, TypeScript checks third-party declaration files such as Zod's .d.cts types, which use default-import syntax internally. Turning it off would surface errors in dependency types you do not control.

Review the layering order in TSConfig Best Practices.
See how presets compose end to end in the Presets Overview.

Why Use This Preset?

Usage

What This Preset Configures

Related