diff --git a/lib/error_tracker/migration/postgres/v01.ex b/lib/error_tracker/migration/postgres/v01.ex
index bdfb42b..04e8189 100644
--- a/lib/error_tracker/migration/postgres/v01.ex
+++ b/lib/error_tracker/migration/postgres/v01.ex
@@ -6,7 +6,10 @@ defmodule ErrorTracker.Migration.Postgres.V01 do
   def up(%{create_schema: create_schema, prefix: prefix}) do
     if create_schema, do: execute("CREATE SCHEMA IF NOT EXISTS #{prefix}")
 
-    create table(:error_tracker_errors, prefix: prefix) do
+    create table(:error_tracker_errors,
+             primary_key: [name: :id, type: :bigserial],
+             prefix: prefix
+           ) do
       add :kind, :string, null: false
       add :reason, :text, null: false
       add :source_line, :text, null: false
@@ -20,11 +23,16 @@ defmodule ErrorTracker.Migration.Postgres.V01 do
 
     create unique_index(:error_tracker_errors, [:fingerprint], prefix: prefix)
 
-    create table(:error_tracker_occurrences, prefix: prefix) do
+    create table(:error_tracker_occurrences,
+             primary_key: [name: :id, type: :bigserial],
+             prefix: prefix
+           ) do
       add :context, :map, null: false
       add :reason, :text, null: false
       add :stacktrace, :map, null: false
-      add :error_id, references(:error_tracker_errors, on_delete: :delete_all), null: false
+
+      add :error_id, references(:error_tracker_errors, on_delete: :delete_all, type: :bigserial),
+        null: false
 
       timestamps(type: :utc_datetime_usec, updated_at: false)
     end