diff --git a/package.json b/package.json
index d8349ce4a..31e5247eb 100644
--- a/package.json
+++ b/package.json
@@ -68,6 +68,7 @@
     "@types/node": "22.7.4",
     "@types/swagger2openapi": "7.0.4",
     "axios": "1.7.7",
+    "openapi-types": "12.1.3",
     "tsup": "8.3.0",
     "vitest": "2.1.2"
   },
diff --git a/src/code-gen-process.ts b/src/code-gen-process.ts
index a61f0e528..8f22e9fa6 100644
--- a/src/code-gen-process.ts
+++ b/src/code-gen-process.ts
@@ -162,7 +162,7 @@ export class CodeGenProcess {
       fileName: this.config.fileName,
       translateToJavaScript: this.config.toJS,
       customTranslator: this.config.customTranslator
-        ? new this.config.customTranslator(this)
+        ? new this.config.customTranslator()
         : null,
       utils: this.getRenderTemplateData().utils,
     };
diff --git a/src/commands/generate-templates/index.ts b/src/commands/generate-templates/index.ts
index 28cd3f33f..119c551bb 100644
--- a/src/commands/generate-templates/index.ts
+++ b/src/commands/generate-templates/index.ts
@@ -1,8 +1,7 @@
-#!/usr/bin/env node
-
+import type { GenerateTemplatesParams } from "../../../types/index.js";
 import { TemplatesGenProcess } from "./templates-gen-process.js";
 
-export async function generateTemplates(config) {
+export async function generateTemplates(config: GenerateTemplatesParams) {
   const codeGenProcess = new TemplatesGenProcess(config);
   return await codeGenProcess.start();
 }
diff --git a/src/commands/generate-templates/templates-gen-process.ts b/src/commands/generate-templates/templates-gen-process.ts
index 988732260..0bf654898 100644
--- a/src/commands/generate-templates/templates-gen-process.ts
+++ b/src/commands/generate-templates/templates-gen-process.ts
@@ -1,7 +1,10 @@
 import path from "node:path";
 import url from "node:url";
 import { consola } from "consola";
-import type { GenerateTemplatesOutput } from "../../../types/index.js";
+import type {
+  GenerateTemplatesOutput,
+  GenerateTemplatesParams,
+} from "../../../types/index.js";
 import { FileSystem } from "../../util/file-system.js";
 import { TemplatesGenConfig } from "./configuration.js";
 
@@ -22,7 +25,7 @@ export class TemplatesGenProcess {
 
   importTemplatePrefixes = ["@base", "@modular", "@default"];
 
-  constructor(config) {
+  constructor(config: GenerateTemplatesParams) {
     this.config = new TemplatesGenConfig(config);
     this.fileSystem = new FileSystem();
   }
diff --git a/src/component-type-name-resolver.ts b/src/component-type-name-resolver.ts
index 1ced36a9b..0c1f4da5c 100644
--- a/src/component-type-name-resolver.ts
+++ b/src/component-type-name-resolver.ts
@@ -6,7 +6,7 @@ import { getRandomInt } from "./util/random.js";
 export class ComponentTypeNameResolver extends NameResolver {
   counter = 1;
   fallbackNameCounter = 1;
-  countersByVariant = new Map();
+  countersByVariant = new Map<string, number>();
 
   constructor(config: CodeGenConfig, reservedNames: string[]) {
     super(config, reservedNames, (variants) => {
@@ -15,7 +15,8 @@ export class ComponentTypeNameResolver extends NameResolver {
         if (!this.countersByVariant.has(randomVariant)) {
           this.countersByVariant.set(randomVariant, 0);
         }
-        const variantCounter = this.countersByVariant.get(randomVariant) + 1;
+        const variantCounter =
+          (this.countersByVariant.get(randomVariant) as number) + 1;
         this.countersByVariant.set(randomVariant, variantCounter);
         const dirtyResolvedName = `${randomVariant}${variantCounter}`;
         consola.debug(
diff --git a/src/configuration.ts b/src/configuration.ts
index 10631b6dd..e76ad495d 100644
--- a/src/configuration.ts
+++ b/src/configuration.ts
@@ -1,5 +1,6 @@
 import * as cosmiconfig from "cosmiconfig";
 import lodash from "lodash";
+import type { OpenAPI } from "openapi-types";
 import * as typescript from "typescript";
 import type {
   ExtractingOptions,
@@ -9,6 +10,7 @@ import { ComponentTypeNameResolver } from "./component-type-name-resolver.js";
 import * as CONSTANTS from "./constants.js";
 import type { MonoSchemaParser } from "./schema-parser/mono-schema-parser.js";
 import type { SchemaParser } from "./schema-parser/schema-parser.js";
+import type { Translator } from "./translators/translator.js";
 import { objectAssign } from "./util/object-assign.js";
 
 const TsKeyword = {
@@ -162,7 +164,7 @@ export class CodeGenConfig {
   output = "";
   url = "";
   cleanOutput = false;
-  spec = null;
+  spec: OpenAPI.Document | null = null;
   fileName = "Api.ts";
   authorizationToken: string | undefined;
   requestOptions = null;
@@ -215,7 +217,7 @@ export class CodeGenConfig {
     emitDecoratorMetadata: true,
     skipLibCheck: true,
   };
-  customTranslator;
+  customTranslator?: new () => Translator;
 
   Ts = {
     Keyword: structuredClone(TsKeyword),
@@ -334,10 +336,10 @@ export class CodeGenConfig {
   primitiveTypes: Record<
     string,
     | string
-    | ((schema: any, parser: SchemaParser) => string)
+    | ((schema: OpenAPI.Document, parser: SchemaParser) => string)
     | ({ $default: string } & Record<
         string,
-        string | ((schema: any, parser: SchemaParser) => string)
+        string | ((schema: OpenAPI.Document, parser: SchemaParser) => string)
       >)
   > = {
     integer: () => this.Ts.Keyword.Number,
@@ -419,11 +421,7 @@ export class CodeGenConfig {
       this.Ts.Keyword.Boolean,
     ];
     this.jsEmptyTypes = [this.Ts.Keyword.Null, this.Ts.Keyword.Undefined];
-    this.componentTypeNameResolver = new ComponentTypeNameResolver(
-      this,
-      null,
-      [],
-    );
+    this.componentTypeNameResolver = new ComponentTypeNameResolver(this, []);
   }
 
   update = (update: Partial<GenerateApiConfiguration["config"]>) => {
diff --git a/src/schema-walker.ts b/src/schema-walker.ts
index ee9740e7f..9c8248415 100644
--- a/src/schema-walker.ts
+++ b/src/schema-walker.ts
@@ -1,4 +1,5 @@
 import lodash from "lodash";
+import type { OpenAPI } from "openapi-types";
 import type { CodeGenConfig } from "./configuration.js";
 import type { SwaggerSchemaResolver } from "./swagger-schema-resolver.js";
 
@@ -7,8 +8,8 @@ import type { SwaggerSchemaResolver } from "./swagger-schema-resolver.js";
 export class SchemaWalker {
   config: CodeGenConfig;
   swaggerSchemaResolver: SwaggerSchemaResolver;
-  schemas = new Map<string, Record<string, any>>();
-  caches = new Map<string, Record<string, any>>();
+  schemas = new Map<string, OpenAPI.Document>();
+  caches = new Map<string, OpenAPI.Document>();
 
   constructor(
     config: CodeGenConfig,
@@ -18,7 +19,7 @@ export class SchemaWalker {
     this.swaggerSchemaResolver = swaggerSchemaResolver;
   }
 
-  addSchema = (name: string, schema: Record<string, unknown>) => {
+  addSchema = (name: string, schema: OpenAPI.Document) => {
     this.schemas.set(name, structuredClone(schema));
   };
 
diff --git a/src/swagger-schema-resolver.ts b/src/swagger-schema-resolver.ts
index 16e3526da..02ebd43c3 100644
--- a/src/swagger-schema-resolver.ts
+++ b/src/swagger-schema-resolver.ts
@@ -1,6 +1,7 @@
 import { consola } from "consola";
 import * as yaml from "js-yaml";
 import lodash from "lodash";
+import type { OpenAPI, OpenAPIV2 } from "openapi-types";
 import * as swagger2openapi from "swagger2openapi";
 import type { CodeGenConfig } from "./configuration.js";
 import type { FileSystem } from "./util/file-system.js";
@@ -20,7 +21,7 @@ export class SwaggerSchemaResolver {
   async create() {
     const { spec, patch, input, url, authorizationToken } = this.config;
 
-    if (this.config.spec) {
+    if (spec) {
       return await this.convertSwaggerObject(spec, { patch });
     }
 
@@ -35,11 +36,11 @@ export class SwaggerSchemaResolver {
   }
 
   convertSwaggerObject(
-    swaggerSchema: Record<string, unknown>,
+    swaggerSchema: OpenAPI.Document,
     converterOptions: { patch?: boolean },
   ): Promise<{
-    usageSchema: Record<string, any>;
-    originalSchema: Record<string, unknown>;
+    usageSchema: OpenAPI.Document;
+    originalSchema: OpenAPI.Document;
   }> {
     return new Promise((resolve) => {
       const result = structuredClone(swaggerSchema);
@@ -51,11 +52,11 @@ export class SwaggerSchemaResolver {
         result.info,
       );
 
-      if (!result.openapi) {
+      if (!Object.hasOwn(result, "openapi")) {
         result.paths = lodash.merge({}, result.paths);
 
         swagger2openapi.convertObj(
-          result,
+          result as OpenAPIV2.Document,
           {
             ...converterOptions,
             warnOnly: true,
@@ -95,7 +96,7 @@ export class SwaggerSchemaResolver {
   async fetchSwaggerSchemaFile(
     pathToSwagger: string,
     urlToSwagger: string,
-    authToken: string,
+    authToken?: string,
   ) {
     if (this.fileSystem.pathIsExist(pathToSwagger)) {
       return this.getSwaggerSchemaByPath(pathToSwagger);
@@ -103,7 +104,7 @@ export class SwaggerSchemaResolver {
     consola.info(`try to get swagger by URL "${urlToSwagger}"`);
     return await this.request.download({
       url: urlToSwagger,
-      authToken,
+      authToken: authToken,
     });
   }
 
diff --git a/src/templates-worker.ts b/src/templates-worker.ts
index a547201da..98888ccdd 100644
--- a/src/templates-worker.ts
+++ b/src/templates-worker.ts
@@ -171,16 +171,18 @@ export class TemplatesWorker {
       .keys(this.config.templatePaths)
       .find((key) => path_.startsWith(`@${key}`));
 
-    const rawPath = path.resolve(
-      path_.replace(
-        `@${foundTemplatePathKey}`,
-        this.config.templatePaths[foundTemplatePathKey],
-      ),
-    );
-    const fixedPath = this.findTemplateWithExt(rawPath);
+    if (foundTemplatePathKey) {
+      const rawPath = path.resolve(
+        path_.replace(
+          `@${foundTemplatePathKey}`,
+          lodash.get(this.config.templatePaths, foundTemplatePathKey),
+        ),
+      );
+      const fixedPath = this.findTemplateWithExt(rawPath);
 
-    if (fixedPath) {
-      return this.fileSystem.getFileContent(fixedPath);
+      if (fixedPath) {
+        return this.fileSystem.getFileContent(fixedPath);
+      }
     }
 
     const customPath =
diff --git a/src/type-name-formatter.ts b/src/type-name-formatter.ts
index 8704c2dad..11297e933 100644
--- a/src/type-name-formatter.ts
+++ b/src/type-name-formatter.ts
@@ -60,27 +60,28 @@ export class TypeNameFormatter {
     name: string,
     options: { type?: FormattingSchemaType },
   ): string => {
-    const { type } = options || {};
-
     if (!this.isValidName(name)) {
       if (!/^[a-zA-Z_$]/g.test(name)) {
         const fixPrefix =
-          type === "enum-key"
+          options.type === "enum-key"
             ? this.config.fixInvalidEnumKeyPrefix
             : this.config.fixInvalidTypeNamePrefix;
-        name = `${fixPrefix} ${name}`;
+        return `${fixPrefix} ${name}`;
       }
 
       // specific replaces for TSOA 3.x
-      if (name.includes("."))
-        name = name
+      if (name.includes(".")) {
+        return name
           .replace(/Exclude_keyof[A-Za-z]+/g, () => "ExcludeKeys")
           .replace(/%22~AND~%22/g, "And")
           .replace(/%22~OR~%22/g, "Or")
           .replace(/(\.?%22)|\./g, "_")
           .replace(/__+$/, "");
+      }
 
-      if (name.includes("-")) name = lodash.startCase(name).replace(/ /g, "");
+      if (name.includes("-")) {
+        return lodash.startCase(name).replace(/ /g, "");
+      }
     }
 
     return name;
diff --git a/types/index.ts b/types/index.ts
index c36f5e3ea..97204ed89 100644
--- a/types/index.ts
+++ b/types/index.ts
@@ -1,4 +1,6 @@
+import type { ComponentTypeNameResolver } from "../src/component-type-name-resolver.js";
 import type { MonoSchemaParser } from "../src/schema-parser/mono-schema-parser.js";
+import type { Translator } from "../src/translators/translator.js";
 
 type HttpClientType = "axios" | "fetch";
 
@@ -209,7 +211,7 @@ interface GenerateApiParamsBase {
    * }
    * ```
    */
-  customTranslator?: new () => typeof import("../src/translators/translator.js").Translator;
+  customTranslator?: new () => Translator;
   /** fallback name for enum key resolver */
   enumKeyResolverName?: string;
   /** fallback name for type name resolver */
@@ -655,14 +657,11 @@ export interface GenerateApiConfiguration {
     enumKeyResolverName: string;
     typeNameResolverName: string;
     specificArgNameResolverName: string;
-    /** do not use constructor args, it can break functionality of this property, just send class reference */
-    customTranslator?: new (
-      ...args: never[]
-    ) => typeof import("../src/translators/translator.js").Translator;
+    customTranslator?: new () => Translator;
     internalTemplateOptions: {
       addUtilRequiredKeysType: boolean;
     };
-    componentTypeNameResolver: typeof import("../src/component-type-name-resolver.js").ComponentTypeNameResolver;
+    componentTypeNameResolver: ComponentTypeNameResolver;
     fileNames: {
       dataContracts: string;
       routeTypes: string;
diff --git a/yarn.lock b/yarn.lock
index 9a4933db6..308a9c160 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2234,7 +2234,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"openapi-types@npm:^12.1.0":
+"openapi-types@npm:12.1.3, openapi-types@npm:^12.1.0":
   version: 12.1.3
   resolution: "openapi-types@npm:12.1.3"
   checksum: 10c0/4ad4eb91ea834c237edfa6ab31394e87e00c888fc2918009763389c00d02342345195d6f302d61c3fd807f17723cd48df29b47b538b68375b3827b3758cd520f
@@ -2802,6 +2802,7 @@ __metadata:
     js-yaml: "npm:^4.1.0"
     lodash: "npm:^4.17.21"
     nanoid: "npm:^3.3.7"
+    openapi-types: "npm:12.1.3"
     prettier: "npm:~3.3.3"
     swagger-schema-official: "npm:2.0.0-bab6bed"
     swagger2openapi: "npm:^7.0.8"