diff --git a/CHANGELOG.md b/CHANGELOG.md
index eea56e0..4724cbd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,12 @@
 
 All notable changes to this project will be documented in this file.
 
+## [0.2.5] - 2025-03-27
+
+### Changed
+
+- Improved error handling for oneOf, anyOf, allOf
+
 ## [0.2.4] - 2025-03-24
 
 ### Changed
diff --git a/README.md b/README.md
index ec56530..de8165d 100644
--- a/README.md
+++ b/README.md
@@ -72,6 +72,7 @@ Cabidela takes a JSON-Schema and optional configuration flags:
 - `errorMessages`: boolean - If true, the validator will use custom `errorMessage` messages from the schema. Default is false.
 - `fullErrors`: boolean - If true, the validator will be more verbose when throwing errors for complex schemas (example: anyOf, oneOf's), set to false for shorter exceptions. Default is true.
 - `useMerge`: boolean - Set to true if you want to use the `$merge` keyword. Default is false. See below for more information.
+- `usePatch`: boolean - Set to true if you want to use the `$patch` keyword. Default is false. See below for more information.
 - `subSchemas`: any[] - An optional array of sub-schemas that can be used with `$id` and `$ref`. See below for more information.
 
 Returns a validation object.
@@ -299,6 +300,50 @@ new Cabidela(schema, { useMerge: true });
 
 You can combine `$merge` with `$id` and `$ref` keywords, which get resolved first, for even more flexibility.
 
+## $patch
+
+Use can use `$patch` to remove properties from an object.
+
+Here's how it works:
+
+```json
+{
+  "$patch": {
+    "source": {
+      "type": "object",
+      "properties": {
+        "p": { "type": "string" },
+        "q": { "type": "number" }
+      },
+      "additionalProperties": false
+    },
+    "with": {
+      "properties": { "q": null }
+    }
+  }
+}
+```
+
+Resolves to:
+
+```json
+{
+  "type": "object",
+  "properties": {
+    "p": { "type": "string" },
+  },
+  "additionalProperties": false
+}
+```
+
+To use `$patch` set the `usePatch` flag to true when creating the instance.
+
+```js
+new Cabidela(schema, { usePatch: true });
+```
+
+Like `$merge`, you can combine `$patch` with `$id` and `$ref` keywords, which get resolved first, for even more flexibility.
+
 ## Custom errors
 
 If the new instance options has the `errorMessages` flag set to true, you can use the property `errorMessage` in the schema to define custom error messages.
diff --git a/src/helpers.ts b/src/helpers.ts
index 0b05883..2e7ac54 100644
--- a/src/helpers.ts
+++ b/src/helpers.ts
@@ -35,9 +35,26 @@ function deepMerge(target: any, source: any) {
   return result;
 }
 
+function deepPatch(target: any, source: any) {
+  const result = { ...target };
+  for (const key of Object.keys(target)) {
+    if (typeof target[key] == "object" && typeof source[key] == "object") {
+      const patch = deepPatch(target[key], source[key]);
+      if (patch) result[key] = patch;
+      else delete result[key];
+    } else if (source === null) {
+      return null;
+    } else {
+      result[key] = structuredClone(result[key]);
+    }
+  }
+  return result;
+}
+
 export const traverseSchema = (options: CabidelaOptions, definitions: any, obj: any) => {
   const ts = (obj: any, cb?: any) => {
     let hits: number;
+    if (!obj) return;
     do {
       hits = 0;
       for (const key of Object.keys(obj)) {
@@ -57,6 +74,16 @@ export const traverseSchema = (options: CabidelaOptions, definitions: any, obj:
               delete obj[key];
             }
           }
+          if (options.usePatch && key == "$patch") {
+            const merge = deepPatch(obj[key].source, obj[key].with);
+            if (cb) {
+              cb(merge);
+            } else {
+              // root level
+              Object.assign(obj, merge);
+              delete obj[key];
+            }
+          }
         } else {
           if (key == "$ref") {
             const { $id, $path } = parse$ref(obj[key]);
@@ -76,7 +103,7 @@ export const traverseSchema = (options: CabidelaOptions, definitions: any, obj:
           }
         }
       }
-    } while (hits > 0);
+    } while (obj && hits > 0);
   };
   ts(obj);
 };
diff --git a/src/index.ts b/src/index.ts
index 58f67e3..6ae9a4d 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -3,6 +3,7 @@ import { resolvePayload, pathToString, traverseSchema } from "./helpers";
 export type CabidelaOptions = {
   applyDefaults?: boolean;
   useMerge?: boolean;
+  usePatch?: boolean;
   errorMessages?: boolean;
   fullErrors?: boolean;
   subSchemas?: Array<any>;
@@ -30,6 +31,8 @@ export class Cabidela {
     this.options = {
       fullErrors: true,
       subSchemas: [],
+      useMerge: false,
+      usePatch: false,
       applyDefaults: false,
       errorMessages: false,
       ...(options || {}),
@@ -43,7 +46,7 @@ export class Cabidela {
         this.addSchema(subSchema, false);
       }
     }
-    if (this.options.useMerge || (this.options.subSchemas as []).length > 0) {
+    if (this.options.useMerge || this.options.usePatch || (this.options.subSchemas as []).length > 0) {
       traverseSchema(this.options, this.definitions, this.schema);
     }
   }
@@ -139,7 +142,7 @@ export class Cabidela {
     if (needle.schema.hasOwnProperty("maxProperties")) {
       if (Object.keys(needle.payload).length > needle.schema.maxProperties) {
         this.throw(
-          `maxProperties at '${pathToString(needle.path)}' is ${needle.schema.minProperties}, got ${Object.keys(needle.payload).length}`,
+          `maxProperties at '${pathToString(needle.path)}' is ${needle.schema.maxProperties}, got ${Object.keys(needle.payload).length}`,
           needle,
         );
       }
@@ -207,7 +210,7 @@ export class Cabidela {
           absorvErrors: true,
           deferredApplyDefaults: true,
         });
-        rounds += matches;
+        rounds++;
         if (breakCondition && breakCondition(rounds)) break;
         defaultsCallbacks.push(...needle.defaultsCallbacks);
         needle.defaultsCallbacks = [];
@@ -247,9 +250,7 @@ export class Cabidela {
     if (needle.schema.hasOwnProperty("oneOf")) {
       const rounds = this.parseList(needle.schema.oneOf, needle, (r: number) => r !== 1);
       if (rounds !== 1) {
-        if (needle.path.length == 0) {
-          this.throw(`oneOf at '${pathToString(needle.path)}' not met, ${rounds} matches`, needle);
-        }
+        this.throw(`oneOf at '${pathToString(needle.path)}' not met, ${rounds} matches found`, needle);
         return 0;
       }
       return 1;
diff --git a/tests/11-patch.test.ts b/tests/11-patch.test.ts
new file mode 100644
index 0000000..067e2dc
--- /dev/null
+++ b/tests/11-patch.test.ts
@@ -0,0 +1,31 @@
+import { expect, describe, test } from "vitest";
+import { FakeCabidela } from "./lib/fake-cabidela";
+
+describe("$patch", () => {
+  test.skipIf(process.env.AJV)("two objects", () => {
+    let schema = {
+      $patch: {
+        source: {
+          type: "object",
+          properties: {
+            p: { type: "string" },
+            q: { type: "number" },
+          },
+          additionalProperties: false,
+        },
+        with: {
+          properties: { q: null },
+        },
+      },
+    };
+    const cabidela = new FakeCabidela(schema, { usePatch: true });
+    schema = cabidela.getSchema();
+    expect(schema).toStrictEqual({
+      type: "object",
+      properties: {
+        p: { type: "string" },
+      },
+      additionalProperties: false,
+    });
+  });
+});
diff --git a/tests/60-error-messages.test.ts b/tests/60-error-messages.test.ts
index 42166b6..17ea347 100644
--- a/tests/60-error-messages.test.ts
+++ b/tests/60-error-messages.test.ts
@@ -89,13 +89,13 @@ describe("errorMessages oneOf", () => {
       cabidela.validate({
         missing: "property",
       }),
-    ).toThrowError(/oneOf at '.' not met, 0 matches: prompt required, messages required/);
+    ).toThrowError(/oneOf at '\/' not met, 0 matches found: prompt required, messages required/);
   });
   test.skipIf(process.env.AJV)("messages need role and content", () => {
     expect(() =>
       cabidela.validate({
         messages: [{ role: "user" }],
       }),
-    ).toThrowError(/oneOf at '.' not met, 0 matches: prompt required, messages need both role and content/);
+    ).toThrowError(/oneOf at '\/' not met, 0 matches found: prompt required, messages need both role and content/);
   });
 });