diff --git a/src/index.js b/src/index.js
index 3bc35a1..04268ce 100644
--- a/src/index.js
+++ b/src/index.js
@@ -19,15 +19,16 @@ const {
 } = require("./utils.js");
 const worker = require("./worker");
 
-/** @typedef {import("schema-utils/declarations/validate").Schema} Schema */
+/** @typedef {import("schema-utils").Schema} Schema */
 /** @typedef {import("webpack").WebpackPluginInstance} WebpackPluginInstance */
 /** @typedef {import("webpack").Compiler} Compiler */
 /** @typedef {import("webpack").Compilation} Compilation */
-/** @typedef {import("webpack").WebpackError} WebpackError */
 /** @typedef {import("webpack").Asset} Asset */
 /** @typedef {import("webpack").AssetInfo} AssetInfo */
 /** @typedef {import("webpack").sources.Source} Source */
 /** @typedef {import("webpack").Module} Module */
+/** @typedef {import("webpack").TemplatePath} TemplatePath */
+/** @typedef {import("webpack").PathData} PathData */
 /** @typedef {import("./utils.js").imageminMinify} ImageminMinifyFunction */
 /** @typedef {import("./utils.js").squooshMinify} SquooshMinifyFunction */
 
@@ -41,16 +42,7 @@ const worker = require("./worker");
  * @returns {boolean}
  */
 
-// eslint-disable-next-line jsdoc/no-restricted-syntax
-/**
- * @typedef {object} ImageminOptions
- * @property {Array<string | [string, Record<string, any>?] | import("imagemin").Plugin>} plugins plugins
- */
-
-// eslint-disable-next-line jsdoc/no-restricted-syntax
-/**
- * @typedef {{ [key: string]: any }} SquooshOptions
- */
+/** @typedef {typeof import("./worker").isFilenameProcessed} IsFilenameProcessed */
 
 /**
  * @typedef {object} WorkerResult
@@ -58,7 +50,7 @@ const worker = require("./worker");
  * @property {Buffer} data data buffer
  * @property {Array<Error>} warnings warnings
  * @property {Array<Error>} errors errors
- * @property {AssetInfo} info asset info
+ * @property {AssetInfo & { [worker.isFilenameProcessed]?: boolean }} info asset info
  */
 
 /**
@@ -114,11 +106,6 @@ const worker = require("./worker");
  * @typedef {BasicTransformerImplementation<T> & BasicTransformerHelpers} TransformerFunction
  */
 
-/**
- * @typedef {object} PathData
- * @property {string=} filename filename
- */
-
 /**
  * @callback FilenameFn
  * @param {PathData} pathData path data
@@ -155,7 +142,7 @@ const worker = require("./worker");
  * @property {Buffer} input input buffer
  * @property {Transformer<T> | Transformer<T>[]} transformer transformer
  * @property {string=} severityError severity error setting
- * @property {(filenameTemplate: string, options: { filename: string }) => string=} generateFilename filename generator function
+ * @property {(filename: TemplatePath, data: PathData) => string} generateFilename filename generator function
  */
 
 /**
@@ -169,7 +156,7 @@ const worker = require("./worker");
  * @property {Rule=} test test to match files against
  * @property {Rule=} include files to include
  * @property {Rule=} exclude files to exclude
- * @property {T extends any[] ? { [P in keyof T]: Minimizer<T[P]> } : Minimizer<T> | Minimizer<T>[]=} minimizer allows to setup the minimizer
+ * @property {T extends any[] ? { [P in keyof T]: Minimizer<T[P]> } : Minimizer<T> | Minimizer<T>[]=} minimizer allows to set the minimizer
  * @property {G extends any[] ? { [P in keyof G]: Generator<G[P]> } : Generator<G>[]=} generator allows to set the generator
  * @property {boolean=} loader automatically adding `image-loader`.
  * @property {number=} concurrency maximum number of concurrency optimization processes in one time
@@ -328,6 +315,7 @@ class ImageMinimizerPlugin {
 
     // In some cases cpus() returns undefined
     // https://github.com/nodejs/node/issues/19022
+    // TODO fix me
     const limit = Math.max(
       1,
       this.options.concurrency ?? os.cpus()?.length ?? 1,
@@ -372,15 +360,9 @@ class ImageMinimizerPlugin {
         });
       }
 
-      compilation.warnings = [
-        ...compilation.warnings,
-        .../** @type {[WebpackError]} */ (output.warnings),
-      ];
+      compilation.warnings = [...compilation.warnings, ...output.warnings];
 
-      compilation.errors = [
-        ...compilation.errors,
-        .../** @type {[WebpackError]} */ (output.errors),
-      ];
+      compilation.errors = [...compilation.errors, ...output.errors];
 
       if (compilation.getAsset(output.filename)) {
         compilation.updateAsset(
@@ -459,7 +441,7 @@ class ImageMinimizerPlugin {
   }
 
   /**
-   * @param {import("webpack").Compiler} compiler compiler
+   * @param {Compiler} compiler compiler
    */
   apply(compiler) {
     const pluginName = this.constructor.name;
diff --git a/src/loader.js b/src/loader.js
index 88c18e5..88f35b8 100644
--- a/src/loader.js
+++ b/src/loader.js
@@ -57,10 +57,10 @@ function processSizeQuery(transformers, widthQuery, heightQuery, unitQuery) {
   return transformers.map((transformer) => {
     const minimizer = { ...transformer };
 
-    const minimizerOptions =
-      /** @type { import("./index").BasicTransformerOptions<T> & { resize?: import("./index").ResizeOptions }} */
-      // @ts-expect-error
-      { ...minimizer.options };
+    const minimizerOptions = {
+      .../** @type {{ options: import("./index").BasicTransformerOptions<T> & { resize?: import("./index").ResizeOptions  }}} */
+      (minimizer).options,
+    };
 
     minimizerOptions.resize = { ...minimizerOptions?.resize };
     minimizer.options = minimizerOptions;
diff --git a/src/utils.js b/src/utils.js
index 2b09f71..8dbadb0 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -1,12 +1,14 @@
 const path = require("node:path");
 
 /** @typedef {import("./index").WorkerResult} WorkerResult */
-/** @typedef {import("./index").SquooshOptions} SquooshOptions */
-/** @typedef {import("imagemin").Options} ImageminOptions */
+/** @typedef {import("./index").CustomOptions} CustomOptions */
 /** @typedef {import("webpack").WebpackError} WebpackError */
 /** @typedef {import("webpack").Module} Module */
 /** @typedef {import("webpack").AssetInfo} AssetInfo */
 
+// eslint-disable-next-line jsdoc/no-restricted-syntax
+/** @typedef {any} EXPECTED_ANY */
+
 /**
  * @template T
  * @typedef {() => Promise<T>} Task
@@ -515,9 +517,8 @@ class InvalidConfigError extends Error {
 }
 
 /**
- * @template T
- * @param {ImageminOptions} imageminConfig imagemin configuration
- * @returns {Promise<ImageminOptions>} normalized imagemin configuration
+ * @param {Record<string, EXPECTED_ANY>} imageminConfig imagemin configuration
+ * @returns {Promise<Record<string, EXPECTED_ANY>>} normalized imagemin configuration
  */
 async function imageminNormalizeConfig(imageminConfig) {
   if (
@@ -603,24 +604,28 @@ async function imageminNormalizeConfig(imageminConfig) {
 }
 
 /**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} minimizerOptions minimizer options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} generated result
  */
-async function imageminGenerate(original, minimizerOptions) {
-  const minimizerOptionsNormalized = /** @type {ImageminOptions} */ (
-    await imageminNormalizeConfig(
-      /** @type {ImageminOptions} */ (minimizerOptions ?? {}),
-    )
-  );
+async function imageminGenerate(original, options) {
+  /** @typedef {import("imagemin").Options} ImageminOptions */
+
+  const optionsNormalized =
+    /** @type {ImageminOptions} */
+    (
+      await imageminNormalizeConfig(
+        /** @type {ImageminOptions} */
+        (options ?? {}),
+      )
+    );
 
   const imagemin = (await import("imagemin")).default;
 
   let result;
 
   try {
-    result = await imagemin.buffer(original.data, minimizerOptionsNormalized);
+    result = await imagemin.buffer(original.data, optionsNormalized);
   } catch (error) {
     const originalError =
       error instanceof Error ? error : new Error(/** @type {string} */ (error));
@@ -656,24 +661,28 @@ async function imageminGenerate(original, minimizerOptions) {
 }
 
 /**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} options options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} minified result
  */
 async function imageminMinify(original, options) {
-  const minimizerOptionsNormalized = /** @type {ImageminOptions} */ (
-    await imageminNormalizeConfig(
-      /** @type {ImageminOptions} */ (options ?? {}),
-    )
-  );
+  /** @typedef {import("imagemin").Options} ImageminOptions */
+
+  const optionsNormalized =
+    /** @type {ImageminOptions} */
+    (
+      await imageminNormalizeConfig(
+        /** @type {ImageminOptions} */
+        (options ?? {}),
+      )
+    );
 
   const imagemin = (await import("imagemin")).default;
 
   let result;
 
   try {
-    result = await imagemin.buffer(original.data, minimizerOptionsNormalized);
+    result = await imagemin.buffer(original.data, optionsNormalized);
   } catch (error) {
     const originalError =
       error instanceof Error ? error : new Error(/** @type {string} */ (error));
@@ -783,20 +792,22 @@ async function squooshImagePoolTeardown() {
 }
 
 /**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} minifyOptions minify options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} generated result
  */
-async function squooshGenerate(original, minifyOptions) {
+async function squooshGenerate(original, options) {
+  // eslint-disable-next-line jsdoc/no-restricted-syntax
+  /**
+   * @typedef {{ [key: string]: any }} SquooshOptions
+   */
+
   const squoosh = require("@squoosh/lib");
 
   const isReusePool = Boolean(pool);
   const imagePool = pool || squooshImagePoolCreate();
   const image = imagePool.ingestImage(new Uint8Array(original.data));
-
-  const squooshOptions = /** @type {SquooshOptions} */ (minifyOptions ?? {});
-
+  const squooshOptions = /** @type {SquooshOptions} */ (options ?? {});
   const preprocEntries = Object.entries(squooshOptions).filter(
     ([key, value]) => {
       if (key === "resize" && value?.enabled === false) {
@@ -879,12 +890,16 @@ squooshGenerate.setup = squooshImagePoolSetup;
 squooshGenerate.teardown = squooshImagePoolTeardown;
 
 /**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} options minify options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} minified result
  */
 async function squooshMinify(original, options) {
+  // eslint-disable-next-line jsdoc/no-restricted-syntax
+  /**
+   * @typedef {{ [key: string]: any }} SquooshOptions
+   */
+
   const squoosh = require("@squoosh/lib");
 
   const { encoders } = squoosh;
@@ -979,35 +994,6 @@ squooshMinify.setup = squooshImagePoolSetup;
 
 squooshMinify.teardown = squooshImagePoolTeardown;
 
-/** @typedef {import("sharp")} SharpLib */
-/** @typedef {import("sharp").Sharp} Sharp */
-/** @typedef {import("sharp").ResizeOptions & { enabled?: boolean; unit?: "px" | "percent" }} ResizeOptions */
-
-/**
- * @typedef {object} SharpEncodeOptions
- * @property {import("sharp").AvifOptions=} avif AVIF options
- * @property {import("sharp").GifOptions=} gif GIF options
- * @property {import("sharp").HeifOptions=} heif HEIF options
- * @property {import("sharp").JpegOptions=} jpeg JPEG options
- * @property {import("sharp").JpegOptions=} jpg JPG options
- * @property {import("sharp").PngOptions=} png PNG options
- * @property {import("sharp").WebpOptions=} webp WebP options
- */
-
-/**
- * @typedef SharpFormat
- * @type {keyof SharpEncodeOptions}
- */
-
-// TODO remove the `SizeSuffix` option in the next major release, because we support `[width]` and `[height]`
-/**
- * @typedef {object} SharpOptions
- * @property {ResizeOptions=} resize resize options
- * @property {number | 'auto'=} rotate rotate options
- * @property {SizeSuffix=} sizeSuffix size suffix
- * @property {SharpEncodeOptions=} encodeOptions encode options
- */
-
 /**
  * @typedef SizeSuffix
  * @type {(width: number, height: number) => string}
@@ -1051,17 +1037,15 @@ const SHARP_MINIFY_FORMATS = new Map([
   ["webp", "webp"],
 ]);
 
+/** @typedef {EXPECTED_ANY} CustomSharpFormat */
+
 /**
  * @param {WorkerResult} original original original worker result
- * @param {SharpOptions} minimizerOptions minify options
- * @param {SharpFormat | null} targetFormat target format
+ * @param {CustomOptions=} options options
+ * @param {CustomSharpFormat | null=} targetFormat target format
  * @returns {Promise<WorkerResult | null>} transformed result
  */
-async function sharpTransform(
-  original,
-  minimizerOptions = {},
-  targetFormat = null,
-) {
+async function sharpTransform(original, options = {}, targetFormat = null) {
   const inputExt = path.extname(original.filename).slice(1).toLowerCase();
 
   if (
@@ -1080,23 +1064,23 @@ async function sharpTransform(
     return null;
   }
 
-  /** @type {SharpLib} */
+  /** @type {import("sharp")} */
   const sharp = require("sharp");
 
   const imagePipeline = sharp(original.data, { animated: true });
 
   // ====== rotate ======
 
-  if (typeof minimizerOptions.rotate === "number") {
-    imagePipeline.rotate(minimizerOptions.rotate);
-  } else if (minimizerOptions.rotate === "auto") {
+  if (typeof options.rotate === "number") {
+    imagePipeline.rotate(options.rotate);
+  } else if (options.rotate === "auto") {
     imagePipeline.rotate();
   }
 
   // ====== resize ======
 
-  if (minimizerOptions.resize) {
-    const { enabled = true, unit = "px", ...params } = minimizerOptions.resize;
+  if (options.resize) {
+    const { enabled = true, unit = "px", ...params } = options.resize;
 
     if (
       enabled &&
@@ -1136,10 +1120,26 @@ async function sharpTransform(
 
   const imageMetadata = await imagePipeline.metadata();
 
+  /**
+   * @typedef {object} SharpEncodeOptions
+   * @property {import("sharp").AvifOptions=} avif AVIF options
+   * @property {import("sharp").GifOptions=} gif GIF options
+   * @property {import("sharp").HeifOptions=} heif HEIF options
+   * @property {import("sharp").JpegOptions=} jpeg JPEG options
+   * @property {import("sharp").JpegOptions=} jpg JPG options
+   * @property {import("sharp").PngOptions=} png PNG options
+   * @property {import("sharp").WebpOptions=} webp WebP options
+   */
+
+  /**
+   * @typedef SharpFormat
+   * @type {keyof SharpEncodeOptions}
+   */
+
   const outputFormat =
     targetFormat ?? /** @type {SharpFormat} */ (imageMetadata.format);
 
-  const encodeOptions = minimizerOptions.encodeOptions?.[outputFormat];
+  const encodeOptions = options.encodeOptions?.[outputFormat];
 
   imagePipeline.toFormat(outputFormat, encodeOptions);
 
@@ -1151,8 +1151,8 @@ async function sharpTransform(
   const { width, height } = result.info;
 
   const sizeSuffix =
-    typeof minimizerOptions.sizeSuffix === "function"
-      ? minimizerOptions.sizeSuffix(width, height)
+    typeof options.sizeSuffix === "function"
+      ? options.sizeSuffix(width, height)
       : "";
 
   const dotIndex = original.filename.lastIndexOf(".");
@@ -1183,17 +1183,41 @@ async function sharpTransform(
 }
 
 /**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} minimizerOptions minify options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} generated result
  */
-function sharpGenerate(original, minimizerOptions) {
-  const sharpOptions = /** @type {SharpOptions} */ (minimizerOptions ?? {});
+function sharpGenerate(original, options) {
+  /**
+   * @typedef {object} SharpEncodeOptions
+   * @property {import("sharp").AvifOptions=} avif AVIF options
+   * @property {import("sharp").GifOptions=} gif GIF options
+   * @property {import("sharp").HeifOptions=} heif HEIF options
+   * @property {import("sharp").JpegOptions=} jpeg JPEG options
+   * @property {import("sharp").JpegOptions=} jpg JPG options
+   * @property {import("sharp").PngOptions=} png PNG options
+   * @property {import("sharp").WebpOptions=} webp WebP options
+   */
 
-  const targetFormats = /** @type {SharpFormat[]} */ (
-    Object.keys(sharpOptions.encodeOptions ?? {})
-  );
+  // TODO remove the `SizeSuffix` option in the next major release, because we support `[width]` and `[height]`
+  /**
+   * @typedef {object} SharpOptions
+   * @property {ResizeOptions=} resize resize options
+   * @property {number | 'auto'=} rotate rotate options
+   * @property {SizeSuffix=} sizeSuffix size suffix
+   * @property {SharpEncodeOptions=} encodeOptions encode options
+   */
+
+  const sharpOptions = /** @type {SharpOptions} */ (options ?? {});
+
+  /**
+   * @typedef SharpFormat
+   * @type {keyof SharpEncodeOptions}
+   */
+
+  const targetFormats =
+    /** @type {SharpFormat[]} */
+    (Object.keys(sharpOptions.encodeOptions ?? {}));
 
   if (targetFormats.length === 0) {
     const error = new Error(
@@ -1219,33 +1243,28 @@ function sharpGenerate(original, minimizerOptions) {
 }
 
 /**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} minimizerOptions minify options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} minified result
  */
-function sharpMinify(original, minimizerOptions) {
-  return sharpTransform(
-    original,
-    /** @type {SharpOptions} */ (minimizerOptions),
-  );
+function sharpMinify(original, options) {
+  return sharpTransform(original, options);
 }
 
-/** @typedef {import("svgo")} SvgoLib */
-/** @typedef {Omit<import("svgo").Config, "path" | "datauri">} SvgoEncodeOptions */
-
 /**
- * @typedef {object} SvgoOptions
- * @property {SvgoEncodeOptions=} encodeOptions encode options
- */
-
-/**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} minimizerOptions minify options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} minified result
  */
-async function svgoMinify(original, minimizerOptions) {
+async function svgoMinify(original, options) {
+  /** @typedef {import("svgo")} SvgoLib */
+  /** @typedef {Omit<import("svgo").Config, "path" | "datauri">} SvgoEncodeOptions */
+
+  /**
+   * @typedef {object} SvgoOptions
+   * @property {SvgoEncodeOptions=} encodeOptions encode options
+   */
+
   if (path.extname(original.filename).toLowerCase() !== ".svg") {
     return null;
   }
@@ -1253,7 +1272,7 @@ async function svgoMinify(original, minimizerOptions) {
   /** @type {SvgoLib} */
   const { optimize } = require("svgo");
 
-  const { encodeOptions } = /** @type {SvgoOptions} */ (minimizerOptions ?? {});
+  const { encodeOptions } = /** @type {SvgoOptions} */ (options ?? {});
 
   /** @type {import("svgo").Output} */
   let result;
diff --git a/src/worker.js b/src/worker.js
index a1aa4dc..f816365 100644
--- a/src/worker.js
+++ b/src/worker.js
@@ -1,6 +1,7 @@
 /** @typedef {import("./index").WorkerResult} WorkerResult */
 /** @typedef {import("./index").FilenameFn} FilenameFn */
 
+/** @type {unique symbol} */
 const isFilenameProcessed = Symbol("isFilenameProcessed");
 
 /**
@@ -11,12 +12,10 @@ const isFilenameProcessed = Symbol("isFilenameProcessed");
  */
 function processFilenameTemplate(result, options, filenameTemplate) {
   if (
-    // @ts-expect-error need to fix
     !result.info[isFilenameProcessed] &&
     typeof filenameTemplate !== "undefined" &&
     typeof options.generateFilename === "function"
   ) {
-    // @ts-expect-error need to fix
     result.filename = options.generateFilename(filenameTemplate, {
       filename: result.filename,
     });
@@ -25,7 +24,6 @@ function processFilenameTemplate(result, options, filenameTemplate) {
       .replaceAll(/\[width\]/gi, result.info.width)
       .replaceAll(/\[height\]/gi, result.info.height);
 
-    // @ts-expect-error need to fix
     result.info[isFilenameProcessed] = true;
   }
 }
@@ -136,3 +134,4 @@ async function worker(options) {
 }
 
 module.exports = worker;
+module.exports.isFilenameProcessed = isFilenameProcessed;
diff --git a/types/index.d.ts b/types/index.d.ts
index 63927af..f3a7029 100644
--- a/types/index.d.ts
+++ b/types/index.d.ts
@@ -29,9 +29,9 @@ declare class ImageMinimizerPlugin<T, G = T> {
    */
   private teardownAll;
   /**
-   * @param {import("webpack").Compiler} compiler compiler
+   * @param {Compiler} compiler compiler
    */
-  apply(compiler: import("webpack").Compiler): void;
+  apply(compiler: Compiler): void;
 }
 declare namespace ImageMinimizerPlugin {
   export {
@@ -48,18 +48,18 @@ declare namespace ImageMinimizerPlugin {
     WebpackPluginInstance,
     Compiler,
     Compilation,
-    WebpackError,
     Asset,
     AssetInfo,
     Source,
     Module,
+    TemplatePath,
+    PathData,
     ImageminMinifyFunction,
     SquooshMinifyFunction,
     Rule,
     Rules,
     FilterFn,
-    ImageminOptions,
-    SquooshOptions,
+    IsFilenameProcessed,
     WorkerResult,
     Task,
     CustomOptions,
@@ -69,7 +69,6 @@ declare namespace ImageMinimizerPlugin {
     BasicTransformerImplementation,
     BasicTransformerHelpers,
     TransformerFunction,
-    PathData,
     FilenameFn,
     Transformer,
     Minimizer,
@@ -88,31 +87,22 @@ import { squooshGenerate } from "./utils.js";
 import { sharpMinify } from "./utils.js";
 import { sharpGenerate } from "./utils.js";
 import { svgoMinify } from "./utils.js";
-type Schema = import("schema-utils/declarations/validate").Schema;
+type Schema = import("schema-utils").Schema;
 type WebpackPluginInstance = import("webpack").WebpackPluginInstance;
 type Compiler = import("webpack").Compiler;
 type Compilation = import("webpack").Compilation;
-type WebpackError = import("webpack").WebpackError;
 type Asset = import("webpack").Asset;
 type AssetInfo = import("webpack").AssetInfo;
 type Source = import("webpack").sources.Source;
 type Module = import("webpack").Module;
+type TemplatePath = import("webpack").TemplatePath;
+type PathData = import("webpack").PathData;
 type ImageminMinifyFunction = typeof imageminMinify;
 type SquooshMinifyFunction = typeof squooshMinify;
 type Rule = RegExp | string;
 type Rules = Rule[] | Rule;
 type FilterFn = (source: Buffer, sourcePath: string) => boolean;
-type ImageminOptions = {
-  /**
-   * plugins
-   */
-  plugins: Array<
-    string | [string, Record<string, any>?] | import("imagemin").Plugin
-  >;
-};
-type SquooshOptions = {
-  [key: string]: any;
-};
+type IsFilenameProcessed = typeof import("./worker").isFilenameProcessed;
 type WorkerResult = {
   /**
    * filename
@@ -133,7 +123,9 @@ type WorkerResult = {
   /**
    * asset info
    */
-  info: AssetInfo;
+  info: AssetInfo & {
+    [worker.isFilenameProcessed]?: boolean;
+  };
 };
 type Task<T> = {
   /**
@@ -204,12 +196,6 @@ type BasicTransformerHelpers = {
 };
 type TransformerFunction<T> = BasicTransformerImplementation<T> &
   BasicTransformerHelpers;
-type PathData = {
-  /**
-   * filename
-   */
-  filename?: string | undefined;
-};
 type FilenameFn = (
   pathData: PathData,
   assetInfo?: AssetInfo | undefined,
@@ -266,14 +252,7 @@ type InternalWorkerOptions<T> = {
   /**
    * filename generator function
    */
-  generateFilename?:
-    | ((
-        filenameTemplate: string,
-        options: {
-          filename: string;
-        },
-      ) => string)
-    | undefined;
+  generateFilename: (filename: TemplatePath, data: PathData) => string;
 };
 type InternalLoaderOptions<T> = import("./loader").LoaderOptions<T>;
 type PluginOptions<T, G> = {
@@ -290,7 +269,7 @@ type PluginOptions<T, G> = {
    */
   exclude?: Rule | undefined;
   /**
-   * allows to setup the minimizer
+   * allows to set the minimizer
    */
   minimizer?:
     | (T extends any[]
@@ -320,3 +299,4 @@ type PluginOptions<T, G> = {
    */
   deleteOriginalAssets?: boolean | undefined;
 };
+import worker = require("./worker");
diff --git a/types/utils.d.ts b/types/utils.d.ts
index c319695..8c74933 100644
--- a/types/utils.d.ts
+++ b/types/utils.d.ts
@@ -1,19 +1,12 @@
 export type WorkerResult = import("./index").WorkerResult;
-export type SquooshOptions = import("./index").SquooshOptions;
-export type ImageminOptions = import("imagemin").Options;
+export type CustomOptions = import("./index").CustomOptions;
 export type WebpackError = import("webpack").WebpackError;
 export type Module = import("webpack").Module;
 export type AssetInfo = import("webpack").AssetInfo;
+export type EXPECTED_ANY = any;
 export type Task<T> = () => Promise<T>;
 export type FunctionReturning<T> = () => T;
-export type SvgoLib = typeof import("svgo");
-export type SvgoEncodeOptions = Omit<import("svgo").Config, "path" | "datauri">;
-export type SvgoOptions = {
-  /**
-   * encode options
-   */
-  encodeOptions?: SvgoEncodeOptions | undefined;
-};
+export type CustomSharpFormat = EXPECTED_ANY;
 export type Uint8ArrayUtf8ByteString = (
   array: number[] | Uint8Array,
   start: number,
@@ -69,94 +62,36 @@ export type SquooshImagePool = {
    */
   close: () => Promise<void>;
 };
-export type SharpLib = typeof import("sharp");
-export type Sharp = import("sharp").Sharp;
-export type ResizeOptions = import("sharp").ResizeOptions & {
-  enabled?: boolean;
-  unit?: "px" | "percent";
-};
-export type SharpEncodeOptions = {
-  /**
-   * AVIF options
-   */
-  avif?: import("sharp").AvifOptions | undefined;
-  /**
-   * GIF options
-   */
-  gif?: import("sharp").GifOptions | undefined;
-  /**
-   * HEIF options
-   */
-  heif?: import("sharp").HeifOptions | undefined;
-  /**
-   * JPEG options
-   */
-  jpeg?: import("sharp").JpegOptions | undefined;
-  /**
-   * JPG options
-   */
-  jpg?: import("sharp").JpegOptions | undefined;
-  /**
-   * PNG options
-   */
-  png?: import("sharp").PngOptions | undefined;
-  /**
-   * WebP options
-   */
-  webp?: import("sharp").WebpOptions | undefined;
-};
-export type SharpFormat = keyof SharpEncodeOptions;
-export type SharpOptions = {
-  /**
-   * resize options
-   */
-  resize?: ResizeOptions | undefined;
-  /**
-   * rotate options
-   */
-  rotate?: (number | "auto") | undefined;
-  /**
-   * size suffix
-   */
-  sizeSuffix?: SizeSuffix | undefined;
-  /**
-   * encode options
-   */
-  encodeOptions?: SharpEncodeOptions | undefined;
-};
 export type SizeSuffix = (width: number, height: number) => string;
 export const ABSOLUTE_URL_REGEX: RegExp;
 /** @type {WeakMap<Module, AssetInfo>} */
 export const IMAGE_MINIMIZER_PLUGIN_INFO_MAPPINGS: WeakMap<Module, AssetInfo>;
 export const WINDOWS_PATH_REGEX: RegExp;
 /**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} minimizerOptions minimizer options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} generated result
  */
-export function imageminGenerate<T>(
+export function imageminGenerate(
   original: WorkerResult,
-  minimizerOptions: T,
+  options?: CustomOptions | undefined,
 ): Promise<WorkerResult | null>;
 /**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} options options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} minified result
  */
-export function imageminMinify<T>(
+export function imageminMinify(
   original: WorkerResult,
-  options: T,
+  options?: CustomOptions | undefined,
 ): Promise<WorkerResult | null>;
 /**
- * @template T
- * @param {ImageminOptions} imageminConfig imagemin configuration
- * @returns {Promise<ImageminOptions>} normalized imagemin configuration
+ * @param {Record<string, EXPECTED_ANY>} imageminConfig imagemin configuration
+ * @returns {Promise<Record<string, EXPECTED_ANY>>} normalized imagemin configuration
  */
-export function imageminNormalizeConfig<T>(
-  imageminConfig: ImageminOptions,
-): Promise<ImageminOptions>;
+export function imageminNormalizeConfig(
+  imageminConfig: Record<string, EXPECTED_ANY>,
+): Promise<Record<string, EXPECTED_ANY>>;
 /**
  * @param {string} url URL
  * @returns {boolean} true when URL is absolute, otherwise false
@@ -173,11 +108,11 @@ export function isAbsoluteURL(url: string): boolean;
  */
 export function memoize<T>(fn: FunctionReturning<T>): FunctionReturning<T>;
 /** @typedef {import("./index").WorkerResult} WorkerResult */
-/** @typedef {import("./index").SquooshOptions} SquooshOptions */
-/** @typedef {import("imagemin").Options} ImageminOptions */
+/** @typedef {import("./index").CustomOptions} CustomOptions */
 /** @typedef {import("webpack").WebpackError} WebpackError */
 /** @typedef {import("webpack").Module} Module */
 /** @typedef {import("webpack").AssetInfo} AssetInfo */
+/** @typedef {any} EXPECTED_ANY */
 /**
  * @template T
  * @typedef {() => Promise<T>} Task
@@ -189,68 +124,57 @@ export function memoize<T>(fn: FunctionReturning<T>): FunctionReturning<T>;
  */
 export function replaceFileExtension(filename: string, ext: string): string;
 /**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} minimizerOptions minify options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} generated result
  */
-export function sharpGenerate<T>(
+export function sharpGenerate(
   original: WorkerResult,
-  minimizerOptions: T,
+  options?: CustomOptions | undefined,
 ): Promise<WorkerResult | null>;
 /**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} minimizerOptions minify options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} minified result
  */
-export function sharpMinify<T>(
+export function sharpMinify(
   original: WorkerResult,
-  minimizerOptions: T,
+  options?: CustomOptions | undefined,
 ): Promise<WorkerResult | null>;
 /**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} minifyOptions minify options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} generated result
  */
-export function squooshGenerate<T>(
+export function squooshGenerate(
   original: WorkerResult,
-  minifyOptions: T,
+  options?: CustomOptions | undefined,
 ): Promise<WorkerResult | null>;
 export namespace squooshGenerate {
   export { squooshImagePoolSetup as setup };
   export { squooshImagePoolTeardown as teardown };
 }
 /**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} options minify options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} minified result
  */
-export function squooshMinify<T>(
+export function squooshMinify(
   original: WorkerResult,
-  options: T,
+  options?: CustomOptions | undefined,
 ): Promise<WorkerResult | null>;
 export namespace squooshMinify {
   export { squooshImagePoolSetup as setup };
   export { squooshImagePoolTeardown as teardown };
 }
-/** @typedef {import("svgo")} SvgoLib */
-/** @typedef {Omit<import("svgo").Config, "path" | "datauri">} SvgoEncodeOptions */
-/**
- * @typedef {object} SvgoOptions
- * @property {SvgoEncodeOptions=} encodeOptions encode options
- */
 /**
- * @template T
  * @param {WorkerResult} original original worker result
- * @param {T} minimizerOptions minify options
+ * @param {CustomOptions=} options options
  * @returns {Promise<WorkerResult | null>} minified result
  */
-export function svgoMinify<T>(
+export function svgoMinify(
   original: WorkerResult,
-  minimizerOptions: T,
+  options?: CustomOptions | undefined,
 ): Promise<WorkerResult | null>;
 /**
  * Run tasks with limited concurrency.
diff --git a/types/worker.d.ts b/types/worker.d.ts
index f71838c..7201d3c 100644
--- a/types/worker.d.ts
+++ b/types/worker.d.ts
@@ -8,7 +8,11 @@ declare function worker<T>(
   options: import("./index").InternalWorkerOptions<T>,
 ): Promise<WorkerResult>;
 declare namespace worker {
-  export { WorkerResult, FilenameFn };
+  export { isFilenameProcessed, WorkerResult, FilenameFn };
 }
+/** @typedef {import("./index").WorkerResult} WorkerResult */
+/** @typedef {import("./index").FilenameFn} FilenameFn */
+/** @type {unique symbol} */
+declare const isFilenameProcessed: unique symbol;
 type WorkerResult = import("./index").WorkerResult;
 type FilenameFn = import("./index").FilenameFn;