diff --git a/crdt_sync_dart/lib/src/record.dart b/crdt_sync_dart/lib/src/record.dart
index 5b31756..acc1719 100644
--- a/crdt_sync_dart/lib/src/record.dart
+++ b/crdt_sync_dart/lib/src/record.dart
@@ -38,7 +38,9 @@ class Record {
       (name, field) => MapEntry(name, [field.$1, field.$2.toStr()]),
     ),
     'deleted': deleted,
-    'deletedHlc': deletedHlc?.toStr(),
+    // Wire key is snake_case to match crdt_sync's Python `Record.to_dict` --
+    // this is a cross-language wire format, not a Dart-idiomatic API.
+    'deleted_hlc': deletedHlc?.toStr(),
   };
 
   factory Record.fromJson(Map<String, dynamic> json) {
@@ -47,7 +49,7 @@ class Record {
       final pair = value as List<dynamic>;
       return MapEntry(name, (pair[0], Hlc.fromStr(pair[1] as String)));
     });
-    final deletedHlcStr = json['deletedHlc'] as String?;
+    final deletedHlcStr = json['deleted_hlc'] as String?;
     return Record(
       id: json['id'] as String,
       fields: fields,
diff --git a/crdt_sync_dart/lib/src/sync.dart b/crdt_sync_dart/lib/src/sync.dart
index 946729b..ab4cb5c 100644
--- a/crdt_sync_dart/lib/src/sync.dart
+++ b/crdt_sync_dart/lib/src/sync.dart
@@ -12,9 +12,12 @@ const _defaultFilename = 'log.json';
 /// to `<pathPrefix>/<deviceId>/<filename>`.
 ///
 /// [encode] serializes a merged log for pushing. [decode] parses a remote
-/// device's pushed text back into a log; throwing [FormatException] is
-/// treated as a corrupt/unparsable push, and that device is skipped for
-/// this tick rather than aborting the whole sync.
+/// device's pushed text back into a log; throwing [FormatException] (bad
+/// JSON syntax) or [TypeError] (valid JSON, wrong shape -- e.g. a missing
+/// or mistyped field during [Record.fromJson]) is treated as a
+/// corrupt/unparsable push, and that device is skipped for this tick
+/// rather than aborting the whole sync. Mirrors the Python `sync_log`'s
+/// `(ValueError, KeyError, TypeError)` catch for the same reason.
 Future<Log> syncLog({
   required GitHubClient client,
   required String deviceId,
@@ -36,6 +39,8 @@ Future<Log> syncLog({
       mergedLog = mergeLogs(mergedLog, decode(text));
     } on FormatException {
       continue;
+    } on TypeError {
+      continue;
     }
   }
 
diff --git a/crdt_sync_dart/test/record_test.dart b/crdt_sync_dart/test/record_test.dart
index 24bebaa..cfc45a7 100644
--- a/crdt_sync_dart/test/record_test.dart
+++ b/crdt_sync_dart/test/record_test.dart
@@ -138,4 +138,35 @@ void main() {
       expect(Record.fromJson(record.toJson()), equals(record));
     });
   });
+
+  group('cross-language wire format', () {
+    // Pins the exact wire shape shared with crdt-sync's Python Record.
+    // These values are duplicated verbatim in the Python package's
+    // `test_record.py` (`TestCrossLanguageWireFormat`). If this test and
+    // that one both pass, the two languages agree on the wire format; if
+    // only one changes, the two suites diverge and at least one of them
+    // fails -- catching exactly the kind of key-naming mismatch
+    // (`deleted_hlc` vs `deletedHlc`) that neither language's own
+    // round-trip test can see on its own.
+    test('matches the fixture shared with the Python package', () {
+      final record = Record(
+        id: 'abc123',
+        fields: {
+          'text': ('hello', Hlc(wallTimeMs: 100, counter: 0, nodeId: 'pc')),
+        },
+        deleted: true,
+        deletedHlc: Hlc(wallTimeMs: 1000, counter: 0, nodeId: 'node-a'),
+      );
+      final expected = {
+        'id': 'abc123',
+        'fields': {
+          'text': ['hello', '1970-01-01T00:00:00.100Z-0000-pc'],
+        },
+        'deleted': true,
+        'deleted_hlc': '1970-01-01T00:00:01.000Z-0000-node-a',
+      };
+      expect(record.toJson(), equals(expected));
+      expect(Record.fromJson(expected), equals(record));
+    });
+  });
 }
diff --git a/crdt_sync_dart/test/sync_test.dart b/crdt_sync_dart/test/sync_test.dart
index c906d80..84204d1 100644
--- a/crdt_sync_dart/test/sync_test.dart
+++ b/crdt_sync_dart/test/sync_test.dart
@@ -146,6 +146,31 @@ void main() {
       expect(putCalls, hasLength(1));
     });
 
+    test('skips a device whose pushed JSON has the wrong shape', () async {
+      // Valid JSON that isn't a record map (e.g. from an incompatible
+      // writer) must be skipped like corrupt JSON, not crash the whole
+      // sync -- this is what the `on TypeError` catch in `syncLog` is
+      // for, not just JSON syntax errors caught by `FormatException`.
+      final (:client, :putCalls) = _client(
+        contentResponses: {
+          'devices': _directoryOf(['phone']),
+          'devices/phone/log.json': _fileContaining('{"a": 5}'),
+        },
+      );
+
+      final merged = await syncLog(
+        client: client,
+        deviceId: 'pc',
+        pathPrefix: 'devices',
+        localLog: {},
+        encode: _encode,
+        decode: _decode,
+      );
+
+      expect(merged, isEmpty);
+      expect(putCalls, hasLength(1));
+    });
+
     test('merges in a remote device\'s entries', () async {
       final remoteLog = <String, Record>{
         'b': Record(id: 'b', fields: {'text': ('from phone', _make(100))}),