diff --git a/src/test/java/dev/iakunin/codexiabot/hackernews/cron/GapsFillerIntegrationTest.java b/src/test/java/dev/iakunin/codexiabot/hackernews/cron/GapsFillerIntegrationTest.java
index 7189c6bd..c9c35c13 100644
--- a/src/test/java/dev/iakunin/codexiabot/hackernews/cron/GapsFillerIntegrationTest.java
+++ b/src/test/java/dev/iakunin/codexiabot/hackernews/cron/GapsFillerIntegrationTest.java
@@ -1,13 +1,94 @@
 package dev.iakunin.codexiabot.hackernews.cron;
 
+import com.github.database.rider.core.api.dataset.DataSet;
+import com.github.database.rider.core.api.dataset.ExpectedDataSet;
 import dev.iakunin.codexiabot.AbstractIntegrationTest;
+import dev.iakunin.codexiabot.util.WireMockServer;
+import dev.iakunin.codexiabot.util.wiremock.Request;
+import dev.iakunin.codexiabot.util.wiremock.Response;
+import dev.iakunin.codexiabot.util.wiremock.Stub;
+import org.cactoos.io.ResourceOf;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.util.TestPropertyValues;
+import org.springframework.context.ApplicationContextInitializer;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.test.context.ContextConfiguration;
 
+@ContextConfiguration(initializers = GapsFillerIntegrationTest.Initializer.class)
 public class GapsFillerIntegrationTest extends AbstractIntegrationTest {
 
     @Autowired
     private GapsFiller gapsFiller;
 
-    // @todo #10 Implement GapsFillerIntegrationTest
+    @Test
+    @DataSet(
+        value = "db-rider/hackernews/cron/gaps-filler/initial/emptyDatabase.yml",
+        cleanBefore = true, cleanAfter = true
+    )
+    @ExpectedDataSet("db-rider/hackernews/cron/gaps-filler/expected/emptyDatabase.yml")
+    public void emptyDatabase() {
+        gapsFiller.run();
+    }
 
+    @Test
+    @DataSet(
+        value = "db-rider/hackernews/cron/gaps-filler/initial/oneMissing.yml",
+        cleanBefore = true, cleanAfter = true
+    )
+    @ExpectedDataSet("db-rider/hackernews/cron/gaps-filler/expected/oneMissing.yml")
+    public void oneMissing() {
+        WireMockServer.stub(
+            new Stub(
+                new Request("/item/2.json"),
+                new Response(
+                    new ResourceOf("wiremock/hackernews/cron/gaps-filler/2.json")
+                )
+            )
+        );
+
+        gapsFiller.run();
+    }
+
+    @Test
+    @DataSet(
+        value = "db-rider/hackernews/cron/gaps-filler/initial/twoMissing.yml",
+        cleanBefore = true, cleanAfter = true
+    )
+    @ExpectedDataSet("db-rider/hackernews/cron/gaps-filler/expected/twoMissing.yml")
+    public void twoMissing() {
+        WireMockServer.stub(
+            new Stub(
+                new Request("/item/2.json"),
+                new Response(
+                    new ResourceOf("wiremock/hackernews/cron/gaps-filler/2.json")
+                )
+            )
+        );
+        WireMockServer.stub(
+            new Stub(
+                new Request("/item/4.json"),
+                new Response(
+                    new ResourceOf("wiremock/hackernews/cron/gaps-filler/4.json")
+                )
+            )
+        );
+
+        gapsFiller.run();
+    }
+
+    @AfterEach
+    void after() {
+        WireMockServer.getInstance().resetAll();
+    }
+
+    static class Initializer implements ApplicationContextInitializer<ConfigurableApplicationContext> {
+        @Override
+        public void initialize(ConfigurableApplicationContext applicationContext) {
+            TestPropertyValues.of(
+                "app.hackernews.base-url=" + WireMockServer.getInstance().baseUrl()
+            ).applyTo(applicationContext.getEnvironment());
+        }
+    }
 }
diff --git a/src/test/resources/db-rider/hackernews/cron/gaps-filler/expected/emptyDatabase.yml b/src/test/resources/db-rider/hackernews/cron/gaps-filler/expected/emptyDatabase.yml
new file mode 100644
index 00000000..598ffa20
--- /dev/null
+++ b/src/test/resources/db-rider/hackernews/cron/gaps-filler/expected/emptyDatabase.yml
@@ -0,0 +1 @@
+hackernews_item: []
diff --git a/src/test/resources/db-rider/hackernews/cron/gaps-filler/expected/oneMissing.yml b/src/test/resources/db-rider/hackernews/cron/gaps-filler/expected/oneMissing.yml
new file mode 100644
index 00000000..0f0dcf81
--- /dev/null
+++ b/src/test/resources/db-rider/hackernews/cron/gaps-filler/expected/oneMissing.yml
@@ -0,0 +1,25 @@
+hackernews_item:
+    -
+        external_id: 1
+        type: story
+        by: test1author
+        title: Title for test1
+        url: test 1 url
+        time: 2009-01-15 05:56:17
+        deleted: false
+    -
+        external_id: 3
+        type: story
+        by: test3author
+        title: Title for test3
+        url: test 3 url
+        time: 2009-01-15 05:58:12
+        deleted: false
+    -
+        external_id: 2
+        type: story
+        by: test2author
+        title: Title for test2
+        url: test 2 url
+        time: 2009-01-15 06:12:49
+        deleted: false
diff --git a/src/test/resources/db-rider/hackernews/cron/gaps-filler/expected/twoMissing.yml b/src/test/resources/db-rider/hackernews/cron/gaps-filler/expected/twoMissing.yml
new file mode 100644
index 00000000..c886bc80
--- /dev/null
+++ b/src/test/resources/db-rider/hackernews/cron/gaps-filler/expected/twoMissing.yml
@@ -0,0 +1,41 @@
+hackernews_item:
+    -
+        external_id: 1
+        type: story
+        by: test1author
+        title: Title for test1
+        url: test 1 url
+        time: 2009-01-15 05:56:17
+        deleted: false
+    -
+        external_id: 3
+        type: story
+        by: test3author
+        title: Title for test3
+        url: test 3 url
+        time: 2009-01-15 05:58:12
+        deleted: false
+    -
+        external_id: 5
+        type: story
+        by: test5author
+        title: Title for test5
+        url: test 5 url
+        time: 2009-01-15 06:32:52
+        deleted: false
+    -
+        external_id: 2
+        type: story
+        by: test2author
+        title: Title for test2
+        url: test 2 url
+        time: 2009-01-15 06:12:49
+        deleted: false
+    -
+        external_id: 4
+        type: story
+        by: test4author
+        title: Title for test4
+        url: test 4 url
+        time: 2009-01-15 06:12:53
+        deleted: false
diff --git a/src/test/resources/db-rider/hackernews/cron/gaps-filler/initial/emptyDatabase.yml b/src/test/resources/db-rider/hackernews/cron/gaps-filler/initial/emptyDatabase.yml
new file mode 100644
index 00000000..598ffa20
--- /dev/null
+++ b/src/test/resources/db-rider/hackernews/cron/gaps-filler/initial/emptyDatabase.yml
@@ -0,0 +1 @@
+hackernews_item: []
diff --git a/src/test/resources/db-rider/hackernews/cron/gaps-filler/initial/oneMissing.yml b/src/test/resources/db-rider/hackernews/cron/gaps-filler/initial/oneMissing.yml
new file mode 100644
index 00000000..71e5df0c
--- /dev/null
+++ b/src/test/resources/db-rider/hackernews/cron/gaps-filler/initial/oneMissing.yml
@@ -0,0 +1,17 @@
+hackernews_item:
+    -
+        external_id: 1
+        type: story
+        by: test1author
+        title: Title for test1
+        url: test 1 url
+        time: 2009-01-15 05:56:17
+        deleted: false
+    -
+        external_id: 3
+        type: story
+        by: test3author
+        title: Title for test3
+        url: test 3 url
+        time: 2009-01-15 05:58:12
+        deleted: false
diff --git a/src/test/resources/db-rider/hackernews/cron/gaps-filler/initial/twoMissing.yml b/src/test/resources/db-rider/hackernews/cron/gaps-filler/initial/twoMissing.yml
new file mode 100644
index 00000000..37288ac6
--- /dev/null
+++ b/src/test/resources/db-rider/hackernews/cron/gaps-filler/initial/twoMissing.yml
@@ -0,0 +1,25 @@
+hackernews_item:
+    -
+        external_id: 1
+        type: story
+        by: test1author
+        title: Title for test1
+        url: test 1 url
+        time: 2009-01-15 05:56:17
+        deleted: false
+    -
+        external_id: 3
+        type: story
+        by: test3author
+        title: Title for test3
+        url: test 3 url
+        time: 2009-01-15 05:58:12
+        deleted: false
+    -
+        external_id: 5
+        type: story
+        by: test5author
+        title: Title for test5
+        url: test 5 url
+        time: 2009-01-15 06:32:52
+        deleted: false
diff --git a/src/test/resources/wiremock/hackernews/cron/gaps-filler/2.json b/src/test/resources/wiremock/hackernews/cron/gaps-filler/2.json
new file mode 100644
index 00000000..f36420c0
--- /dev/null
+++ b/src/test/resources/wiremock/hackernews/cron/gaps-filler/2.json
@@ -0,0 +1,11 @@
+{
+  "by": "test2author",
+  "id": 2,
+  "text": "Some awesome text for test 2.",
+  "title": "Title for test2",
+  "url": "test 2 url",
+  "time": 1231999969,
+  "type": "story",
+  "descendants": 0,
+  "score": 2
+}
diff --git a/src/test/resources/wiremock/hackernews/cron/gaps-filler/4.json b/src/test/resources/wiremock/hackernews/cron/gaps-filler/4.json
new file mode 100644
index 00000000..7581b84c
--- /dev/null
+++ b/src/test/resources/wiremock/hackernews/cron/gaps-filler/4.json
@@ -0,0 +1,11 @@
+{
+  "by": "test4author",
+  "id": 4,
+  "text": "Some awesome text for test 4.",
+  "title": "Title for test4",
+  "url": "test 4 url",
+  "time": 1231999973,
+  "type": "story",
+  "descendants": 30,
+  "score": 55
+}