diff --git a/backend/src/main/kotlin/dev/dres/api/rest/types/evaluation/ApiViewerState.kt b/backend/src/main/kotlin/dev/dres/api/rest/types/evaluation/ApiViewerState.kt
new file mode 100644
index 000000000..49c52020c
--- /dev/null
+++ b/backend/src/main/kotlin/dev/dres/api/rest/types/evaluation/ApiViewerState.kt
@@ -0,0 +1,46 @@
+package dev.dres.api.rest.types.evaluation
+
+import dev.dres.api.rest.types.evaluation.scores.ApiScore
+import dev.dres.api.rest.types.evaluation.scores.ApiTeamGroupValue
+import dev.dres.api.rest.types.evaluation.submission.ApiSubmission
+import dev.dres.api.rest.types.template.team.ApiTeamGroup
+import dev.dres.data.model.run.interfaces.EvaluationId
+import dev.dres.data.model.run.interfaces.TaskId
+import dev.dres.data.model.template.task.TaskTemplateId
+import kotlinx.serialization.Serializable
+
+/**
+ * A DTO to transfer the initial state to the viewer.
+ * Contains all relevant information for the viewer to initiate itself.
+ */
+@Serializable
+data class ApiViewerState(
+    /** The [EvaluationId] of the evaluation this state represents */
+    val evaluationId: EvaluationId,
+    /** The name of the evaluation this state represents */
+    val evaluationName: String,
+    /** The [ApiTeamInfo]s related to this evaluation */
+    val teamInfos: List<ApiTeamInfo>,
+    /** The [ApiTeamGroup]s of this evaluation */
+    val teamGroups: List<ApiTeamGroup>,
+    /** The [ApiTeamGroupValue]s associated with the [ApiTeamGroup]s */
+    val teamGroupValue: List<ApiTeamGroupValue>,
+
+    /** The [ApiScore]s of the active task */
+    val taskScores: List<ApiScore>,
+    /** The [ApiScore]s, grouped for the entire evaluation */
+    val evaluationScores: Map<String, List<ApiScore>>, // ApiScoreOverview had taskGroup in it
+
+    /** The [TaskId] of the current task. Could also only be selected task so far */
+    val activeTaskId: TaskId,
+    /** The [TaskTemplateId] of the current task. */
+    val activeTaskTemplateId: TaskTemplateId,
+    /** The time elapsed so far */
+    val timeElapsed: Long,
+    /** The time remaining. Null means the task is perpetually running */
+    val timeRemaining: Long?, // Prepare perpetual task
+    /** The [ApiTaskStatus] of the currently active task */
+    val activeTaskStatus: ApiTaskStatus,
+    /** The [ApiSubmission]s related to the currently active task */
+    val submissionsOverview: List<ApiSubmission>
+)
diff --git a/backend/src/main/kotlin/dev/dres/api/rest/types/evaluation/scores/ApiScore.kt b/backend/src/main/kotlin/dev/dres/api/rest/types/evaluation/scores/ApiScore.kt
index b86f5b451..03880a653 100644
--- a/backend/src/main/kotlin/dev/dres/api/rest/types/evaluation/scores/ApiScore.kt
+++ b/backend/src/main/kotlin/dev/dres/api/rest/types/evaluation/scores/ApiScore.kt
@@ -1,6 +1,7 @@
 package dev.dres.api.rest.types.evaluation.scores
 
 import dev.dres.data.model.template.team.TeamId
+import kotlinx.serialization.Serializable
 
 /**
  * A container class to track scores per team.
@@ -8,4 +9,5 @@ import dev.dres.data.model.template.team.TeamId
  * @author Ralph Gasser
  * @version 1.0.0
  */
-data class ApiScore(val teamId: TeamId, val score: Double)
\ No newline at end of file
+@Serializable
+data class ApiScore(val teamId: TeamId, val score: Double)
diff --git a/backend/src/main/kotlin/dev/dres/api/rest/types/evaluation/scores/ApiTeamGroupValue.kt b/backend/src/main/kotlin/dev/dres/api/rest/types/evaluation/scores/ApiTeamGroupValue.kt
index fd163bbb0..4a0679480 100644
--- a/backend/src/main/kotlin/dev/dres/api/rest/types/evaluation/scores/ApiTeamGroupValue.kt
+++ b/backend/src/main/kotlin/dev/dres/api/rest/types/evaluation/scores/ApiTeamGroupValue.kt
@@ -1,6 +1,9 @@
 package dev.dres.api.rest.types.evaluation.scores
 
+import kotlinx.serialization.Serializable
+
 /**
  *
  */
+@Serializable
 data class ApiTeamGroupValue(val name: String, val value: Double)