diff --git a/.travis.yml b/.travis.yml
index a1ace24..161fdae 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,9 +6,7 @@ cache:
 notifications:
   email: false
 node_js:
-  - '4'
-before_install:
-  - npm i -g npm@^2.0.0
+  - '6'
 before_script:
   - npm prune
 after_success:
diff --git a/src/migrations/molecules/merge/index.js b/src/migrations/molecules/merge/index.js
index feb54bc..95e05cf 100644
--- a/src/migrations/molecules/merge/index.js
+++ b/src/migrations/molecules/merge/index.js
@@ -9,7 +9,7 @@ const merge = (path, value, subject) => Object.keys(value).reduce(
             return merge([...path, key], value[key], subject);
         }
 
-        return $set([...resolveObjectPath(path), ...key], value[key], subject);
+        return $set([...resolveObjectPath(path), key], value[key], subject);
     },
     subject
 );
diff --git a/src/migrations/molecules/merge/index.spec.js b/src/migrations/molecules/merge/index.spec.js
index a8594c4..52e698b 100644
--- a/src/migrations/molecules/merge/index.spec.js
+++ b/src/migrations/molecules/merge/index.spec.js
@@ -103,6 +103,36 @@ describe('Migrations > Atoms > $merge', () => {
             const subject = undefined;
             expect($merge('some.path', {some: 'value'}, subject)).to.be.an('undefined');
         });
+
+		it('should not split up keys in deep object structures (bugfix #12)', () => {
+			const subject = {
+				test: {
+					a: {
+						b: {
+							cdef: 'c'
+						}
+					}
+				}
+			};
+			const result = $merge('test', {
+				a: {
+					b: {
+						cdef: 'foo'
+					}
+				}
+			}, subject);
+
+			expect(result.test.a.b.c).to.be.an('undefined');
+			expect(result).to.deep.equal({
+				test: {
+					a: {
+						b: {
+							cdef: 'foo'
+						}
+					}
+				}
+			});
+		});
     });
 
     describe('Immutable', () => {
diff --git a/src/util/resolveObjectPath/index.js b/src/util/resolveObjectPath/index.js
index b189319..f540d7e 100644
--- a/src/util/resolveObjectPath/index.js
+++ b/src/util/resolveObjectPath/index.js
@@ -13,7 +13,7 @@ export default path => {
     return path.split('.').map(part => {
         const partAsInteger = parseInt(part);
 
-        if (!isNaN(partAsInteger)) {
+        if (!isNaN(partAsInteger) && String(partAsInteger) === part) {
             return partAsInteger;
         }
 
diff --git a/src/util/resolveObjectPath/index.spec.js b/src/util/resolveObjectPath/index.spec.js
index 50b64b8..34fad49 100644
--- a/src/util/resolveObjectPath/index.spec.js
+++ b/src/util/resolveObjectPath/index.spec.js
@@ -8,11 +8,13 @@ describe('Internals: resolveObjectPath', () => {
         expect(resolveObjectPath('a.b.c')).to.deep.equal(['a', 'b', 'c']);
         expect(resolveObjectPath('a.b.c.1')).to.deep.equal(['a', 'b', 'c', 1]);
         expect(resolveObjectPath('a.b.c.1.d.0')).to.deep.equal(['a', 'b', 'c', 1, 'd', 0]);
+        expect(resolveObjectPath('a.1.c1.2d.d.0')).to.deep.equal(['a', 1, 'c1', '2d', 'd', 0]);
     });
 
     it('should leave arrays untouched', () => {
         expect(resolveObjectPath(['a'])).to.deep.equal(['a']);
         expect(resolveObjectPath(['a', 1, 'b'])).to.deep.equal(['a', 1, 'b']);
         expect(resolveObjectPath(['a', '2', 'c'])).to.deep.equal(['a', '2', 'c']);
+        expect(resolveObjectPath(['a', '2', 'c', '3d'])).to.deep.equal(['a', '2', 'c', '3d']);
     });
 });