diff --git a/.gitignore b/.gitignore
index 524f096..4c53d44 100644
--- a/.gitignore
+++ b/.gitignore
@@ -22,3 +22,6 @@
 # virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
 hs_err_pid*
 replay_pid*
+
+target
+.idea
diff --git a/src/main/java/io/github/eocqrs/cmig/State.java b/src/main/java/io/github/eocqrs/cmig/State.java
index 35abb90..bc52c3c 100644
--- a/src/main/java/io/github/eocqrs/cmig/State.java
+++ b/src/main/java/io/github/eocqrs/cmig/State.java
@@ -22,10 +22,8 @@
 
 package io.github.eocqrs.cmig;
 
+import io.github.eocqrs.cmig.sha.StateChanges;
 import org.cactoos.Scalar;
-/*
- * @todo #32:30m/DEV design State interface
- */
 
 /**
  * State.
@@ -33,8 +31,9 @@
  * @author Aliaksei Bialiauski (abialiauski.dev@gmail.com)
  * @since 0.0.0
  */
-public interface State extends Scalar<String> {
-
+public interface State extends Scalar<StateChanges> {
+  // @todo #37:2hr/DEV Find several designs for States implementations
   @Override
-  String value() throws Exception;
+  StateChanges value();
+
 }
diff --git a/src/main/java/io/github/eocqrs/cmig/meta/Author.java b/src/main/java/io/github/eocqrs/cmig/meta/Author.java
index f270e99..f4a5159 100644
--- a/src/main/java/io/github/eocqrs/cmig/meta/Author.java
+++ b/src/main/java/io/github/eocqrs/cmig/meta/Author.java
@@ -24,7 +24,7 @@
 
 import com.jcabi.xml.XML;
 import com.jcabi.xml.XMLDocument;
-import org.cactoos.Scalar;
+import org.cactoos.Text;
 import org.cactoos.io.ResourceOf;
 
 /**
@@ -33,7 +33,7 @@
  * @author Aliaksei Bialiauski (abialiauski.dev@gmail.com)
  * @since 0.0.0
  */
-public final class Author implements Scalar<String> {
+public final class Author implements Text {
 
   /**
    * XML.
@@ -75,7 +75,7 @@ public Author(final String name, final String id)
   }
 
   @Override
-  public String value() throws Exception {
+  public String asString() {
     return this.xml.xpath(
       "/states/changeState[@id='%s']/@author"
         .formatted(
diff --git a/src/main/java/io/github/eocqrs/cmig/meta/Names.java b/src/main/java/io/github/eocqrs/cmig/meta/Names.java
index 346dc24..c771c15 100644
--- a/src/main/java/io/github/eocqrs/cmig/meta/Names.java
+++ b/src/main/java/io/github/eocqrs/cmig/meta/Names.java
@@ -76,7 +76,7 @@ public Names(final String name, final String id)
   }
 
   @Override
-  public List<String> value() throws Exception {
+  public List<String> value() {
     return this.xml.xpath(
       "/states/changeState[@id='%s']/files/file/@path"
         .formatted(
diff --git a/src/main/java/io/github/eocqrs/cmig/meta/XpathList.java b/src/main/java/io/github/eocqrs/cmig/meta/XpathList.java
index d2c1164..dec19c0 100644
--- a/src/main/java/io/github/eocqrs/cmig/meta/XpathList.java
+++ b/src/main/java/io/github/eocqrs/cmig/meta/XpathList.java
@@ -35,5 +35,5 @@
 public interface XpathList extends Scalar<List<String>> {
 
   @Override
-  List<String> value() throws Exception;
+  List<String> value();
 }
diff --git a/src/main/java/io/github/eocqrs/cmig/session/Cassandra.java b/src/main/java/io/github/eocqrs/cmig/session/Cassandra.java
index e21a5ae..7f25a26 100644
--- a/src/main/java/io/github/eocqrs/cmig/session/Cassandra.java
+++ b/src/main/java/io/github/eocqrs/cmig/session/Cassandra.java
@@ -37,7 +37,7 @@
 public interface Cassandra extends Scalar<Session>, Closeable {
 
   @Override
-  Session value() throws Exception;
+  Session value();
 
   @Override
   void close() throws IOException;
diff --git a/src/main/java/io/github/eocqrs/cmig/session/Cql.java b/src/main/java/io/github/eocqrs/cmig/session/Cql.java
index b3b5676..4830e3b 100644
--- a/src/main/java/io/github/eocqrs/cmig/session/Cql.java
+++ b/src/main/java/io/github/eocqrs/cmig/session/Cql.java
@@ -33,7 +33,6 @@ public interface Cql {
   /**
    * Apply Query.
    *
-   * @throws Exception if something went wrong.
    */
-  void apply() throws Exception;
+  void apply();
 }
diff --git a/src/main/java/io/github/eocqrs/cmig/session/InFile.java b/src/main/java/io/github/eocqrs/cmig/session/InFile.java
index efd45b3..46eb019 100644
--- a/src/main/java/io/github/eocqrs/cmig/session/InFile.java
+++ b/src/main/java/io/github/eocqrs/cmig/session/InFile.java
@@ -57,12 +57,12 @@ public InFile(
   }
 
   @Override
-  public void apply() throws Exception {
+  public void apply() {
     this.cassandra.value()
       .execute(
         new TextOf(
           new ResourceOf(this.name)
-        ).asString()
+        ).toString()
       );
   }
 }
diff --git a/src/main/java/io/github/eocqrs/cmig/session/Simple.java b/src/main/java/io/github/eocqrs/cmig/session/Simple.java
index d013052..27539bf 100644
--- a/src/main/java/io/github/eocqrs/cmig/session/Simple.java
+++ b/src/main/java/io/github/eocqrs/cmig/session/Simple.java
@@ -25,8 +25,6 @@
 import com.datastax.driver.core.Cluster;
 import com.datastax.driver.core.Session;
 
-import java.io.IOException;
-
 /**
  * Simple Cassandra.
  *
@@ -68,12 +66,12 @@ public Simple(
   }
 
   @Override
-  public Session value() throws Exception {
+  public Session value() {
     return this.cluster.connect();
   }
 
   @Override
-  public void close() throws IOException {
+  public void close() {
     this.cluster.close();
   }
 }
diff --git a/src/main/java/io/github/eocqrs/cmig/sha/Sha.java b/src/main/java/io/github/eocqrs/cmig/sha/Sha.java
index 15ae13b..bc9216c 100644
--- a/src/main/java/io/github/eocqrs/cmig/sha/Sha.java
+++ b/src/main/java/io/github/eocqrs/cmig/sha/Sha.java
@@ -43,10 +43,12 @@ public final class Sha implements Text {
    * State ID.
    */
   private final String id;
+
   /**
    * Master file.
    */
   private final String master;
+
   /**
    * CMIG directory.
    */
diff --git a/src/main/java/io/github/eocqrs/cmig/sha/StateChanges.java b/src/main/java/io/github/eocqrs/cmig/sha/StateChanges.java
index fafe9c0..0426b7a 100644
--- a/src/main/java/io/github/eocqrs/cmig/sha/StateChanges.java
+++ b/src/main/java/io/github/eocqrs/cmig/sha/StateChanges.java
@@ -23,9 +23,9 @@
 package io.github.eocqrs.cmig.sha;
 
 import io.github.eocqrs.cmig.meta.XpathList;
+import lombok.SneakyThrows;
 import org.cactoos.Scalar;
 import org.cactoos.io.ResourceOf;
-import org.cactoos.list.ListOf;
 import ru.l3r8y.UnixizedOf;
 
 import java.util.List;
@@ -60,23 +60,29 @@ public StateChanges(final XpathList lst, final String cmg) {
 
   @Override
   public List<String> value() throws Exception {
-    final List<String> contents = new ListOf<>();
-    final List<String> files = this.list.value();
-    for (final String file : files) {
-      final String content =
-        new UnixizedOf(
-          new ResourceOf(
-            "%s/%s"
-              .formatted(
-                this.cmig,
-                file
-              )
+    return this.list.value()
+      .stream()
+      .map(this::contentOf)
+      .toList();
+  }
+
+  /*
+   * @todo #37:30min/DEV Move to separate class
+   * Create class ContentOf with tests.
+   * This puzzle might be moved into unixized library.
+   */
+  @SneakyThrows
+  private String contentOf(final String file) {
+    return new UnixizedOf(
+      new ResourceOf(
+        "%s/%s"
+          .formatted(
+            this.cmig,
+            file
           )
-        )
-          .asText()
-          .asString();
-      contents.add(content);
-    }
-    return contents;
+      )
+    )
+      .asText()
+      .asString();
   }
 }
diff --git a/src/test/java/io/github/eocqrs/cmig/meta/AuthorTest.java b/src/test/java/io/github/eocqrs/cmig/meta/AuthorTest.java
index a4ff89b..4f2eb29 100644
--- a/src/test/java/io/github/eocqrs/cmig/meta/AuthorTest.java
+++ b/src/test/java/io/github/eocqrs/cmig/meta/AuthorTest.java
@@ -41,7 +41,7 @@ void readsAuthorInfoInRightFormat() throws Exception {
       new Author(
         "cmig/master.xml",
         "1"
-      ).value(),
+      ).asString(),
       new IsEqual<>(
         "test"
       )
diff --git a/src/test/java/it/CassandraIntegration.java b/src/test/java/it/CassandraIntegration.java
index 8db0004..cc56af5 100644
--- a/src/test/java/it/CassandraIntegration.java
+++ b/src/test/java/it/CassandraIntegration.java
@@ -22,7 +22,7 @@
 
 package it;
 
-import org.junit.AfterClass;
+import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.BeforeAll;
 import org.testcontainers.containers.CassandraContainer;
 import org.testcontainers.utility.DockerImageName;
@@ -40,16 +40,16 @@ public abstract class CassandraIntegration {
     new CassandraContainer<>(
       DockerImageName.parse("cassandra:3.11.15")
     ).withExposedPorts(9042);
-  protected static String host;
+  protected static String HOST;
 
   @BeforeAll
   static void beforeAll() {
     CassandraIntegration.CASSANDRA.start();
-    CassandraIntegration.host =
+    CassandraIntegration.HOST =
       CassandraIntegration.CASSANDRA.getHost();
   }
 
-  @AfterClass
+  @AfterAll
   public static void tearDown() {
     CassandraIntegration.CASSANDRA.stop();
   }
diff --git a/src/test/java/it/CassandraRunsIT.java b/src/test/java/it/CassandraRunsIT.java
index 34cd3ad..22f8918 100644
--- a/src/test/java/it/CassandraRunsIT.java
+++ b/src/test/java/it/CassandraRunsIT.java
@@ -39,7 +39,7 @@ final class CassandraRunsIT extends CassandraIntegration {
   void runs() {
     MatcherAssert.assertThat(
       "Cassandra runs",
-      CASSANDRA.isRunning(),
+      CassandraIntegration.CASSANDRA.isRunning(),
       new IsEqual<>(true)
     );
   }
diff --git a/src/test/java/it/InFileIT.java b/src/test/java/it/InFileIT.java
index 96d309b..fcca308 100644
--- a/src/test/java/it/InFileIT.java
+++ b/src/test/java/it/InFileIT.java
@@ -41,8 +41,8 @@ void appliesInRightFormat() {
       () ->
         new InFile(
           new Simple(
-            CassandraIntegration.host,
-            CASSANDRA.getMappedPort(9042)
+            CassandraIntegration.HOST,
+            CassandraIntegration.CASSANDRA.getMappedPort(9042)
           ),
           "cmig/001-initial-keyspace.cql"
         ).apply(),
diff --git a/src/test/java/it/SimpleIT.java b/src/test/java/it/SimpleIT.java
index b6d9974..6e8e1d2 100644
--- a/src/test/java/it/SimpleIT.java
+++ b/src/test/java/it/SimpleIT.java
@@ -37,10 +37,10 @@
 final class SimpleIT extends CassandraIntegration {
 
   @Test
-  void connectsSession() throws Exception {
+  void connectsSession() {
     final Session session = new Simple(
-      CassandraIntegration.host,
-      CASSANDRA.getMappedPort(9042)
+      CassandraIntegration.HOST,
+      CassandraIntegration.CASSANDRA.getMappedPort(9042)
     ).value();
     MatcherAssert.assertThat(
       "Session is not null",