nexus/lib/models/epoch_date_time_converter.dart

import "package:freezed_annotation/freezed_annotation.dart";

class EpochDateTimeConverter implements JsonConverter<DateTime, int> {
  const EpochDateTimeConverter();

  @override
  DateTime fromJson(int json) => DateTime.fromMillisecondsSinceEpoch(json);

  @override
  int toJson(DateTime object) => object.millisecondsSinceEpoch;
}