diff --git a/.env.example b/.env.example
new file mode 100644
index 0000000..e62e2c2
--- /dev/null
+++ b/.env.example
@@ -0,0 +1 @@
+DATABASE_URL=sqlite://db.sqlite
diff --git a/.gitignore b/.gitignore
index 9de1006..91d5b1c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -40,3 +40,4 @@ result
 # Added by cargo
 
 /target
+*.sqlite
diff --git a/migrations/0001_relay-labels.down.sql b/migrations/0001_relay-labels.down.sql
new file mode 100644
index 0000000..3acc4bd
--- /dev/null
+++ b/migrations/0001_relay-labels.down.sql
@@ -0,0 +1 @@
+DROP TABLE IF EXISTS RelayLabels;
diff --git a/migrations/0001_relay-labels.up.sql b/migrations/0001_relay-labels.up.sql
new file mode 100644
index 0000000..ae6dc9d
--- /dev/null
+++ b/migrations/0001_relay-labels.up.sql
@@ -0,0 +1,4 @@
+CREATE TABLE IF NOT EXISTS RelayLabels (
+  relay_id INTEGER PRIMARY KEY CHECK(relay_id BETWEEN 1 AND 8),
+  label TEXT NOT NULL CHECK(length(label) <= 50)
+);
diff --git a/specs/001-modbus-relay-control/tasks.md b/specs/001-modbus-relay-control/tasks.md
index 10bd34c..fcb30a6 100644
--- a/specs/001-modbus-relay-control/tasks.md
+++ b/specs/001-modbus-relay-control/tasks.md
@@ -35,7 +35,7 @@
   - **Test**: Settings::new() loads config without errors
   - **Complexity**: Low | **Uncertainty**: Low
 
-- [ ] **T005** [P] [Setup] [TDD] Add SQLite schema file
+- [x] **T005** [P] [Setup] [TDD] Add SQLite schema file
   - Create infrastructure/persistence/schema.sql with relay_labels table
   - Table: `relay_labels (relay_id INTEGER PRIMARY KEY CHECK(relay_id BETWEEN 1 AND 8), label TEXT NOT NULL CHECK(length(label) <= 50))`
   - **Test**: Schema file syntax is valid SQL