diff --git a/src/main/java/database/maker/MakerInfoProvider.java b/src/main/java/database/maker/MakerInfoProvider.java
index 3a0092c217..e418af84d7 100644
--- a/src/main/java/database/maker/MakerInfoProvider.java
+++ b/src/main/java/database/maker/MakerInfoProvider.java
@@ -13,6 +13,9 @@ public class MakerInfoProvider {
     private final Map<Integer, MakerRecipe> recipeCache = new ConcurrentHashMap<>();
 
     public MakerInfoProvider(MakerDao makerDao) {
+        if (makerDao == null) {
+            throw new IllegalArgumentException("MakerDao is null");
+        }
         this.makerDao = makerDao;
     }
 
diff --git a/src/test/java/database/maker/MakerInfoProviderTest.java b/src/test/java/database/maker/MakerInfoProviderTest.java
new file mode 100644
index 0000000000..97df426db2
--- /dev/null
+++ b/src/test/java/database/maker/MakerInfoProviderTest.java
@@ -0,0 +1,125 @@
+package database.maker;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import testutil.AnyValues;
+
+import java.util.Optional;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.Mockito.*;
+
+class MakerInfoProviderTest {
+
+    @Mock
+    private MakerDao makerDao;
+
+    private MakerInfoProvider makerInfoProvider;
+
+    @BeforeEach
+    void reset() {
+        MockitoAnnotations.openMocks(this);
+        this.makerInfoProvider = new MakerInfoProvider(makerDao);
+    }
+
+    @Test
+    void requireNonNullDao() {
+        assertThrows(IllegalArgumentException.class, () -> new MakerInfoProvider(null));
+    }
+
+    @Test
+    void getReagentFromDb() {
+        int itemId = 5783;
+        MakerReagent reagent = createReagent(itemId);
+        when(makerDao.getReagent(anyInt())).thenReturn(Optional.of(reagent));
+
+        Optional<MakerReagent> retrievedReagent = makerInfoProvider.getMakerReagent(itemId);
+
+        assertTrue(retrievedReagent.isPresent());
+        assertEquals(reagent, retrievedReagent.get());
+    }
+
+    @Test
+    void getCachedReagent() {
+        int itemId = 90123444;
+        MakerReagent reagent = createReagent(itemId);
+        when(makerDao.getReagent(anyInt())).thenReturn(Optional.of(reagent));
+
+        Optional<MakerReagent> firstReagent = makerInfoProvider.getMakerReagent(itemId);
+        Optional<MakerReagent> secondReagent = makerInfoProvider.getMakerReagent(itemId);
+
+        assertTrue(firstReagent.isPresent());
+        assertEquals(reagent, firstReagent.get());
+        assertTrue(secondReagent.isPresent());
+        assertEquals(reagent, secondReagent.get());
+        verify(makerDao, times(1)).getReagent(itemId);
+    }
+
+    private MakerReagent createReagent(int itemId) {
+        return new MakerReagent(itemId, "incPAD", 3);
+    }
+
+    @Test
+    void getRecipeFromDb() {
+        int itemId = 43893;
+        MakerRecipe recipe = createRecipe(itemId);
+        when(makerDao.getRecipe(itemId)).thenReturn(Optional.of(recipe));
+
+        Optional<MakerRecipe> retrievedRecipe = makerInfoProvider.getMakerRecipe(itemId);
+
+        assertTrue(retrievedRecipe.isPresent());
+        assertEquals(recipe, retrievedRecipe.get());
+    }
+
+    @Test
+    void getRecipeFromDb_notFound() {
+        when(makerDao.getRecipe(anyInt())).thenReturn(Optional.empty());
+
+        Optional<MakerRecipe> recipe = makerInfoProvider.getMakerRecipe(AnyValues.integer());
+
+        assertTrue(recipe.isEmpty());
+    }
+
+    @Test
+    void getCachedRecipe() {
+        int itemId = 10848;
+        MakerRecipe recipe = createRecipe(itemId);
+        when(makerDao.getRecipe(anyInt())).thenReturn(Optional.of(recipe));
+
+        Optional<MakerRecipe> firstRecipe = makerInfoProvider.getMakerRecipe(itemId);
+        Optional<MakerRecipe> secondRecipe = makerInfoProvider.getMakerRecipe(itemId);
+
+        assertTrue(firstRecipe.isPresent());
+        assertEquals(recipe, firstRecipe.get());
+        assertTrue(secondRecipe.isPresent());
+        assertEquals(recipe, secondRecipe.get());
+        verify(makerDao, times(1)).getRecipe(itemId);
+    }
+
+    private MakerRecipe createRecipe(int itemId) {
+        return new MakerRecipe(itemId, (short) 0, (short) 45, (short) 1, 100_000, null, null, null, (short) 1, (short) 1);
+    }
+
+    @Test
+    void getStimulant() {
+        int catalyst = 4031200;
+        MakerRecipe recipeWithCatalyst = new MakerRecipe(0, (short) 0, (short) 0, (short) 0, 0, null, null, catalyst, (short) 0, (short) 0);
+        when(makerDao.getRecipe(anyInt())).thenReturn(Optional.of(recipeWithCatalyst));
+
+        Optional<Integer> stimulant = makerInfoProvider.getStimulant(AnyValues.integer());
+
+        assertTrue(stimulant.isPresent());
+        assertEquals(catalyst, stimulant.get());
+    }
+
+    @Test
+    void getStimulant_noRecipe() {
+        when(makerDao.getRecipe(anyInt())).thenReturn(Optional.empty());
+
+        Optional<Integer> stimulant = makerInfoProvider.getStimulant(AnyValues.integer());
+
+        assertTrue(stimulant.isEmpty());
+    }
+}
diff --git a/src/test/java/testutil/AnyValues.java b/src/test/java/testutil/AnyValues.java
index ccf9c0abbf..509f379b50 100644
--- a/src/test/java/testutil/AnyValues.java
+++ b/src/test/java/testutil/AnyValues.java
@@ -8,6 +8,10 @@ public class AnyValues {
         return "string";
     }
 
+    public static int integer() {
+        return 17;
+    }
+
     public static DaoException daoException() {
         return new DaoException(string(), new RuntimeException());
     }