diff --git a/packages/openapi-code-generator/src/core/dependency-graph.spec.ts b/packages/openapi-code-generator/src/core/dependency-graph.spec.ts
index 2489a2f4..8292e5ee 100644
--- a/packages/openapi-code-generator/src/core/dependency-graph.spec.ts
+++ b/packages/openapi-code-generator/src/core/dependency-graph.spec.ts
@@ -1,13 +1,13 @@
 import {describe, expect, it} from "@jest/globals"
 import {testVersions, unitTestInput} from "../test/input.test-utils"
 import {buildDependencyGraph} from "./dependency-graph"
-import {getSchemaNameFromRef} from "./openapi-utils"
+import {getNameFromRef} from "./openapi-utils"
 
 describe.each(testVersions)("%s - core/dependency-graph", (version) => {
   it("works", async () => {
     const {input} = await unitTestInput(version)
 
-    const graph = buildDependencyGraph(input, getSchemaNameFromRef)
+    const graph = buildDependencyGraph(input, (it) => getNameFromRef(it, "s_"))
 
     expect(graph.order.indexOf("s_Ordering")).toBeGreaterThan(
       graph.order.indexOf("s_AOrdering"),
diff --git a/packages/openapi-code-generator/src/core/loaders/tsconfig.loader.spec.ts b/packages/openapi-code-generator/src/core/loaders/tsconfig.loader.spec.ts
index 09577fb6..2ec9f81f 100644
--- a/packages/openapi-code-generator/src/core/loaders/tsconfig.loader.spec.ts
+++ b/packages/openapi-code-generator/src/core/loaders/tsconfig.loader.spec.ts
@@ -1,4 +1,4 @@
-import {describe, expect, it} from "@jest/globals"
+import {describe, expect, it, jest} from "@jest/globals"
 import {WebFsAdaptor} from "../file-system/web-fs-adaptor"
 import {loadTsConfigCompilerOptions} from "./tsconfig.loader"
 
@@ -98,4 +98,30 @@ describe("core/loaders/tsconfig.loader", () => {
       rewriteRelativeImportExtensions: true,
     })
   })
+
+  it("falls back to defaults if an exception occurs", async () => {
+    const fs = fsAdaptor({
+      "/virtual/ws/tsconfig.json": JSON.stringify({
+        compilerOptions: {
+          exactOptionalPropertyTypes: true,
+        },
+      }),
+    })
+
+    const spy = jest
+      .spyOn(fs, "readFile")
+      .mockRejectedValue(new Error("EACCES: permission denied"))
+
+    const actual = await loadTsConfigCompilerOptions(
+      "/virtual/ws/packages/pkg",
+      fs,
+    )
+
+    expect(actual).toEqual({
+      exactOptionalPropertyTypes: false,
+      rewriteRelativeImportExtensions: false,
+    })
+
+    expect(spy).toHaveBeenCalled()
+  })
 })
diff --git a/packages/openapi-code-generator/src/core/openapi-loader.spec.ts b/packages/openapi-code-generator/src/core/openapi-loader.spec.ts
index 6875ee19..616634f8 100644
--- a/packages/openapi-code-generator/src/core/openapi-loader.spec.ts
+++ b/packages/openapi-code-generator/src/core/openapi-loader.spec.ts
@@ -2,7 +2,7 @@ import {describe, expect, it} from "@jest/globals"
 import {normalizeRef, pathFromRef} from "./openapi-loader"
 
 describe("core/openapi-loader", () => {
-  describe("normalizeRef", () => {
+  describe("#normalizeRef", () => {
     it("rejects invalid $refs", () => {
       expect(() => normalizeRef("not a ref", "/some/path")).toThrow(
         /invalid \$ref '.+'/,
diff --git a/packages/openapi-code-generator/src/core/openapi-utils.spec.ts b/packages/openapi-code-generator/src/core/openapi-utils.spec.ts
index 0225bb56..3abb08ed 100644
--- a/packages/openapi-code-generator/src/core/openapi-utils.spec.ts
+++ b/packages/openapi-code-generator/src/core/openapi-utils.spec.ts
@@ -1,5 +1,5 @@
 import {describe, expect, it} from "@jest/globals"
-import {getNameFromRef, isRef} from "./openapi-utils"
+import {extractPlaceholders, getNameFromRef, isRef} from "./openapi-utils"
 
 describe("core/openapi-utils", () => {
   describe("#isRef", () => {
@@ -10,6 +10,11 @@ describe("core/openapi-utils", () => {
     it("returns false if $ref is not defined", () => {
       expect(isRef({type: "number"})).toBe(false)
     })
+
+    it("returns false if not passed an object", () => {
+      expect(isRef(null)).toBe(false)
+      expect(isRef(123)).toBe(false)
+    })
   })
 
   describe("#getNameFromRef", () => {
@@ -30,5 +35,29 @@ describe("core/openapi-utils", () => {
         "t_Foo_Bar",
       )
     })
+
+    it("throws on an invalid $ref", () => {
+      expect(() => getNameFromRef({$ref: "#/"}, "t_")).toThrow(
+        "no name found in $ref: '#/'",
+      )
+    })
+  })
+
+  describe("#extractPlaceholders", () => {
+    it("returns an empty array if no placeholders in input", () => {
+      expect(extractPlaceholders("/foo/bar")).toStrictEqual([])
+    })
+
+    it("extracts valid placeholders", () => {
+      expect(extractPlaceholders("/{foo/{id}/bar}/{type}")).toStrictEqual([
+        {
+          placeholder: "id",
+          wholeString: "{id}",
+        },
+        {placeholder: "type", wholeString: "{type}"},
+      ])
+    })
+
+    // todo: expand tests for special characters / escaping
   })
 })
diff --git a/packages/openapi-code-generator/src/core/openapi-utils.ts b/packages/openapi-code-generator/src/core/openapi-utils.ts
index 3eb7f458..6d10e2ef 100644
--- a/packages/openapi-code-generator/src/core/openapi-utils.ts
+++ b/packages/openapi-code-generator/src/core/openapi-utils.ts
@@ -31,7 +31,3 @@ export function extractPlaceholders(
     placeholder: match[1],
   }))
 }
-
-export function getSchemaNameFromRef(reference: Reference) {
-  return getNameFromRef(reference, "s_")
-}
diff --git a/packages/openapi-code-generator/src/core/openapi-validator.spec.ts b/packages/openapi-code-generator/src/core/openapi-validator.spec.ts
index 25ea6b5c..eb65e5dd 100644
--- a/packages/openapi-code-generator/src/core/openapi-validator.spec.ts
+++ b/packages/openapi-code-generator/src/core/openapi-validator.spec.ts
@@ -54,7 +54,7 @@ describe("core/openapi-validator", () => {
     })
   })
 
-  describe.skip("openapi 3.1", () => {
+  describe("openapi 3.1", () => {
     it("should accept a valid specification", async () => {
       const validator = await OpenapiValidator.create()
       await expect(
@@ -89,7 +89,7 @@ describe("core/openapi-validator", () => {
       ).resolves.toBeUndefined()
     })
 
-    it("should reject an invalid specification", async () => {
+    it.skip("should reject an invalid specification", async () => {
       const validator = await OpenapiValidator.create()
       await expect(
         validator.validate(
diff --git a/packages/openapi-code-generator/src/core/openapi-validator.ts b/packages/openapi-code-generator/src/core/openapi-validator.ts
index e83691af..decf4126 100644
--- a/packages/openapi-code-generator/src/core/openapi-validator.ts
+++ b/packages/openapi-code-generator/src/core/openapi-validator.ts
@@ -22,6 +22,8 @@ export class OpenapiValidator {
       return this.validate3_1
     }
 
+    // todo: openapi 3.2: add validator
+
     throw new Error(`unsupported openapi version '${version}'`)
   }
 
diff --git a/packages/openapi-code-generator/src/core/utils.spec.ts b/packages/openapi-code-generator/src/core/utils.spec.ts
index a4e13628..17b4b701 100644
--- a/packages/openapi-code-generator/src/core/utils.spec.ts
+++ b/packages/openapi-code-generator/src/core/utils.spec.ts
@@ -2,6 +2,7 @@ import {describe, expect, it} from "@jest/globals"
 import {
   camelCase,
   coalesce,
+  deepEqual,
   hasSingleElement,
   isDefined,
   isHttpMethod,
@@ -46,6 +47,21 @@ describe("core/utils", () => {
     })
   })
 
+  describe("#deepEqual", () => {
+    it("works for primitives", () => {
+      expect(deepEqual(2, 2)).toBe(true)
+      expect(deepEqual(1, 2)).toBe(false)
+    })
+    it("works for array", () => {
+      expect(deepEqual([1], [1])).toBe(true)
+      expect(deepEqual([1], [2])).toBe(false)
+    })
+    it("works for object", () => {
+      expect(deepEqual({foo: "bar"}, {foo: "bar"})).toBe(true)
+      expect(deepEqual({foo: "bar"}, {foo: "baz"})).toBe(false)
+    })
+  })
+
   describe("#coalesce", () => {
     it("returns the first defined parameter", () => {
       expect(coalesce(null, undefined, 1, 2)).toBe(1)
diff --git a/packages/openapi-code-generator/src/typescript/common/schema-builders/abstract-schema-builder.ts b/packages/openapi-code-generator/src/typescript/common/schema-builders/abstract-schema-builder.ts
index 60737f59..a87b44d1 100644
--- a/packages/openapi-code-generator/src/typescript/common/schema-builders/abstract-schema-builder.ts
+++ b/packages/openapi-code-generator/src/typescript/common/schema-builders/abstract-schema-builder.ts
@@ -15,7 +15,7 @@ import type {
   IRParameter,
   MaybeIRModel,
 } from "../../../core/openapi-types-normalized"
-import {getSchemaNameFromRef, isRef} from "../../../core/openapi-utils"
+import {getNameFromRef, isRef} from "../../../core/openapi-utils"
 import {hasSingleElement} from "../../../core/utils"
 import {CompilationUnit, type ICompilable} from "../compilation-units"
 import type {ImportBuilder} from "../import-builder"
@@ -51,7 +51,8 @@ export abstract class AbstractSchemaBuilder<
     private readonly parent?: SubClass,
   ) {
     this.graph =
-      parent?.graph ?? buildDependencyGraph(this.input, getSchemaNameFromRef)
+      parent?.graph ??
+      buildDependencyGraph(this.input, (it) => this.getSchemaNameFromRef(it))
     this.importHelpers(this.schemaBuilderImports)
     this.typeBuilder = typeBuilder.withImports(this.schemaBuilderImports)
   }
@@ -61,7 +62,7 @@ export abstract class AbstractSchemaBuilder<
   private add(reference: Reference): string {
     this.parent?.add(reference)
 
-    const name = getSchemaNameFromRef(reference)
+    const name = this.getSchemaNameFromRef(reference)
     this.referenced[name] = reference
 
     if (this.imports) {
@@ -148,6 +149,10 @@ export abstract class AbstractSchemaBuilder<
 
   protected abstract importHelpers(importBuilder: ImportBuilder): void
 
+  public getSchemaNameFromRef(reference: Reference) {
+    return getNameFromRef(reference, "s_")
+  }
+
   public abstract schemaTypeForType(type: string): string
 
   protected abstract schemaFromRef(reference: Reference): ExportDefinition
diff --git a/packages/openapi-code-generator/src/typescript/common/schema-builders/joi-schema-builder.ts b/packages/openapi-code-generator/src/typescript/common/schema-builders/joi-schema-builder.ts
index e715eeb6..49639bff 100644
--- a/packages/openapi-code-generator/src/typescript/common/schema-builders/joi-schema-builder.ts
+++ b/packages/openapi-code-generator/src/typescript/common/schema-builders/joi-schema-builder.ts
@@ -8,7 +8,6 @@ import type {
   IRModelString,
   MaybeIRModel,
 } from "../../../core/openapi-types-normalized"
-import {getSchemaNameFromRef} from "../../../core/openapi-utils"
 import {hasSingleElement, isDefined} from "../../../core/utils"
 import type {ImportBuilder} from "../import-builder"
 import type {TypeBuilder} from "../type-builder"
@@ -75,7 +74,7 @@ export class JoiBuilder extends AbstractSchemaBuilder<
   }
 
   protected schemaFromRef(reference: Reference): ExportDefinition {
-    const name = getSchemaNameFromRef(reference)
+    const name = this.getSchemaNameFromRef(reference)
     const schemaObject = this.input.schema(reference)
 
     const value = this.fromModel(schemaObject, true)
diff --git a/packages/openapi-code-generator/src/typescript/common/schema-builders/zod-v3-schema-builder.ts b/packages/openapi-code-generator/src/typescript/common/schema-builders/zod-v3-schema-builder.ts
index bae2b203..8320e2b8 100644
--- a/packages/openapi-code-generator/src/typescript/common/schema-builders/zod-v3-schema-builder.ts
+++ b/packages/openapi-code-generator/src/typescript/common/schema-builders/zod-v3-schema-builder.ts
@@ -8,7 +8,6 @@ import type {
   IRModelString,
   MaybeIRModel,
 } from "../../../core/openapi-types-normalized"
-import {getSchemaNameFromRef} from "../../../core/openapi-utils"
 import {hasSingleElement, isDefined} from "../../../core/utils"
 import type {ImportBuilder} from "../import-builder"
 import type {TypeBuilder} from "../type-builder"
@@ -90,7 +89,7 @@ export class ZodV3Builder extends AbstractSchemaBuilder<
   }
 
   protected schemaFromRef(reference: Reference): ExportDefinition {
-    const name = getSchemaNameFromRef(reference)
+    const name = this.getSchemaNameFromRef(reference)
     const schemaObject = this.input.schema(reference)
 
     const value = this.fromModel(schemaObject, true)
diff --git a/packages/openapi-code-generator/src/typescript/common/schema-builders/zod-v4-schema-builder.ts b/packages/openapi-code-generator/src/typescript/common/schema-builders/zod-v4-schema-builder.ts
index ae0f9d54..ffa0341b 100644
--- a/packages/openapi-code-generator/src/typescript/common/schema-builders/zod-v4-schema-builder.ts
+++ b/packages/openapi-code-generator/src/typescript/common/schema-builders/zod-v4-schema-builder.ts
@@ -8,7 +8,6 @@ import type {
   IRModelString,
   MaybeIRModel,
 } from "../../../core/openapi-types-normalized"
-import {getSchemaNameFromRef} from "../../../core/openapi-utils"
 import {hasSingleElement, isDefined} from "../../../core/utils"
 import type {ImportBuilder} from "../import-builder"
 import type {TypeBuilder} from "../type-builder"
@@ -91,7 +90,7 @@ export class ZodV4Builder extends AbstractSchemaBuilder<
   }
 
   protected schemaFromRef(reference: Reference): ExportDefinition {
-    const name = getSchemaNameFromRef(reference)
+    const name = this.getSchemaNameFromRef(reference)
     const schemaObject = this.input.schema(reference)
 
     const value = this.fromModel(schemaObject, true)