diff --git a/pom.xml b/pom.xml
index 865a4c2..667e963 100644
--- a/pom.xml
+++ b/pom.xml
@@ -6,6 +6,9 @@
     <version>1.7-SNAPSHOT</version>
     <!-- <version>X.Y[-SNAPSHOT]</version> -->
     <packaging>jar</packaging>
+
+    <name>YDB JDBC Importer</name>
+
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <maven.compiler.source>1.8</maven.compiler.source>
@@ -127,7 +130,42 @@
             <scope>test</scope>
         </dependency>
     </dependencies>
+    <build>
+        <resources>
+            <resource>
+                <directory>src/main/resources</directory>
+                <includes>
+                    <include>*.properties</include>
+                </includes>
+                <filtering>true</filtering>
+            </resource>
+            <resource>
+                <directory>src/main/resources</directory>
+                <excludes>
+                    <exclude>*.properties</exclude>
+                </excludes>
+            </resource>
+        </resources>
+    </build>
     <profiles>
+        <profile>
+            <id>jdk8-bootstrap</id>
+            <activation>
+                <jdk>[9</jdk>
+            </activation>
+            <build>
+                <plugins>
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-compiler-plugin</artifactId>
+                        <version>3.13.0</version>
+                        <configuration>
+                            <release>8</release>
+                        </configuration>
+                    </plugin>
+                </plugins>
+            </build>
+        </profile>
         <profile>
             <id>release-profile</id>
             <activation>
@@ -190,4 +228,4 @@
             </build>
         </profile>
     </profiles>
-</project>
\ No newline at end of file
+</project>
diff --git a/src/main/java/tech/ydb/importer/YdbImporter.java b/src/main/java/tech/ydb/importer/YdbImporter.java
index 272ecba..8a9ad3a 100644
--- a/src/main/java/tech/ydb/importer/YdbImporter.java
+++ b/src/main/java/tech/ydb/importer/YdbImporter.java
@@ -2,6 +2,8 @@
 
 import java.io.BufferedWriter;
 import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
 import java.io.OutputStreamWriter;
 import java.nio.charset.StandardCharsets;
 import java.sql.Connection;
@@ -9,10 +11,15 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Properties;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import tech.ydb.importer.config.ImporterConfig;
 import tech.ydb.importer.config.JdomHelper;
@@ -30,18 +37,12 @@
 import tech.ydb.table.values.StructType;
 import tech.ydb.table.values.Type;
 
-import static tech.ydb.importer.config.JdomHelper.isBlank;
-
 /**
  *
  * @author zinal
  */
 public class YdbImporter {
-
-    private static final org.slf4j.Logger LOG = org.slf4j.LoggerFactory.getLogger(YdbImporter.class);
-
-    // X.Y[-SNAPSHOT]
-    public static final String VERSION = "1.7-SNAPSHOT";
+    private static final Logger LOG = LoggerFactory.getLogger(YdbImporter.class);
 
     private final ImporterConfig config;
     private final TableMapList tableMaps;
@@ -76,7 +77,7 @@ public AnyTableLister getTableLister() {
 
     public void run() throws Exception {
         String jdbcClassName = config.getSource().getClassName();
-        if (!isBlank(jdbcClassName)) {
+        if (!JdomHelper.isBlank(jdbcClassName)) {
             LOG.info("Loading driver class {}", jdbcClassName);
             Class.forName(config.getSource().getClassName());
         }
@@ -138,8 +139,7 @@ public void run() throws Exception {
     }
 
     private ExecutorService makeWorkers() {
-        return Executors.newFixedThreadPool(config.getWorkers().getPoolSize(),
-                new WorkerFactory(this));
+        return Executors.newFixedThreadPool(config.getWorkers().getPoolSize(), new WorkerFactory());
     }
 
     private void retrieveSourceMetadata(List<TableDecision> tables, ExecutorService workers)
@@ -257,7 +257,7 @@ private void loadTableData(ExecutorService es, List<TableDecision> tables) throw
     }
 
     public static void main(String[] args) {
-        LOG.info("{} version {}", YdbImporter.class.getSimpleName(), VERSION);
+        LOG.info("{} version {}", YdbImporter.class.getSimpleName(), getVersion());
         if (args.length != 1) {
             LOG.info("Single argument is expected: config-file.xml");
             System.exit(2);
@@ -279,26 +279,31 @@ public static void main(String[] args) {
         }
     }
 
-    public static final class WorkerFactory implements ThreadFactory {
-
-        private final YdbImporter owner;
-        private int counter = 0;
-
-        public WorkerFactory(YdbImporter owner) {
-            this.owner = owner;
+    public static String getVersion() {
+        try {
+            Properties prop = new Properties();
+            InputStream in = YdbImporter.class.getResourceAsStream("/importer_version.properties");
+            prop.load(in);
+            return prop.getProperty("version");
+        } catch (IOException ex) {
+            LOG.error("cannot load version", ex);
+            return "unknown";
         }
+    }
+
+    public static final class WorkerFactory implements ThreadFactory {
+        private final AtomicInteger counter = new AtomicInteger();
 
         @Override
         public Thread newThread(Runnable r) {
+            int workerId = counter.getAndIncrement();
             final Thread t = new Thread(() -> {
-                BlobSaver.initCounter(counter);
+                BlobSaver.initCounter(workerId);
                 r.run();
-            }, "YdbImporter-worker-" + counter);
+            }, "YdbImporter-worker-" + workerId);
             t.setDaemon(false);
-            ++counter;
             return t;
         }
-
     }
 
 }
diff --git a/src/main/resources/importer_version.properties b/src/main/resources/importer_version.properties
new file mode 100644
index 0000000..defbd48
--- /dev/null
+++ b/src/main/resources/importer_version.properties
@@ -0,0 +1 @@
+version=${project.version}
diff --git a/src/main/resources/log4j2.xml b/src/main/resources/log4j2.xml
index 778f684..08f65a0 100644
--- a/src/main/resources/log4j2.xml
+++ b/src/main/resources/log4j2.xml
@@ -2,7 +2,7 @@
 <Configuration>
   <Appenders>
     <Console name="STDOUT" target="SYSTEM_OUT">
-      <PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n"/>
+      <PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss} %-5p %21.21c{1}:%-4L %m%n"/>
     </Console>
   </Appenders>
   <Loggers>
@@ -12,4 +12,4 @@
       <AppenderRef ref="STDOUT"/>
     </Root>
   </Loggers>
-</Configuration>
\ No newline at end of file
+</Configuration>