diff --git a/src/main/kotlin/fr/postgresjson/connexion/Connection.kt b/src/main/kotlin/fr/postgresjson/connexion/Connection.kt
index 8a57b46..9fcd2d6 100644
--- a/src/main/kotlin/fr/postgresjson/connexion/Connection.kt
+++ b/src/main/kotlin/fr/postgresjson/connexion/Connection.kt
@@ -1,7 +1,6 @@
 package fr.postgresjson.connexion
 
 import com.fasterxml.jackson.core.type.TypeReference
-import com.github.jasync.sql.db.Connection
 import com.github.jasync.sql.db.QueryResult
 import com.github.jasync.sql.db.ResultSet
 import com.github.jasync.sql.db.general.ArrayRowData
@@ -14,7 +13,6 @@ import fr.postgresjson.entity.Serializable
 import fr.postgresjson.serializer.Serializer
 import fr.postgresjson.utils.LoggerDelegate
 import org.slf4j.Logger
-import java.util.concurrent.CompletableFuture
 import kotlin.random.Random
 
 typealias SelectOneCallback<T> = QueryResult.(T?) -> Unit
@@ -50,7 +48,15 @@ class Connection(
         connection?.disconnect()
     }
 
-    fun <A> inTransaction(f: (Connection) -> CompletableFuture<A>) = connect().inTransaction(f)
+    fun <A> inTransaction(block: Connection.() -> A?): A? = connect().run {
+        sendQuery("BEGIN")
+        try {
+            block().apply { sendQuery("COMMIT") }
+        } catch (e: Throwable) {
+            sendQuery("ROLLBACK")
+            throw e
+        }
+    }
 
     /**
      * Select One [EntityI] with [List] of parameters
diff --git a/src/main/kotlin/fr/postgresjson/migration/Function.kt b/src/main/kotlin/fr/postgresjson/migration/Function.kt
index 05cca70..20a31dc 100644
--- a/src/main/kotlin/fr/postgresjson/migration/Function.kt
+++ b/src/main/kotlin/fr/postgresjson/migration/Function.kt
@@ -73,8 +73,8 @@ data class Function(
         connection.inTransaction {
             up()
             down()
-            it.sendQuery("ROLLBACK")
-        }.join()
+            sendQuery("ROLLBACK")
+        }
 
         return Status.OK
     }
diff --git a/src/main/kotlin/fr/postgresjson/migration/MigrationScript.kt b/src/main/kotlin/fr/postgresjson/migration/MigrationScript.kt
index 67cbc99..7092879 100644
--- a/src/main/kotlin/fr/postgresjson/migration/MigrationScript.kt
+++ b/src/main/kotlin/fr/postgresjson/migration/MigrationScript.kt
@@ -42,8 +42,8 @@ data class MigrationScript(
         connection.inTransaction {
             up()
             down()
-            it.sendQuery("ROLLBACK")
-        }.join()
+            sendQuery("ROLLBACK")
+        }
 
         return Migration.Status.OK
     }
diff --git a/src/test/kotlin/fr/postgresjson/ConnectionTest.kt b/src/test/kotlin/fr/postgresjson/ConnectionTest.kt
index 4bea302..a388552 100644
--- a/src/test/kotlin/fr/postgresjson/ConnectionTest.kt
+++ b/src/test/kotlin/fr/postgresjson/ConnectionTest.kt
@@ -360,4 +360,20 @@ class ConnectionTest : TestAbstract() {
             assertEquals("myName", rows[0].getString(0))
         }
     }
+
+    @Test
+    fun `select one in transaction`() {
+        connection.inTransaction {
+            selectOne<ObjTestWithParameterObject>(
+                "SELECT json_build_object('first', :first::json, 'second', :second::json)",
+                mapOf(
+                    "first" to ParameterObject("one"),
+                    "second" to ParameterObject("two")
+                )
+            ).let { result ->
+                assertEquals("one", result!!.first.third)
+                assertEquals("two", result.second.third)
+            }
+        }
+    }
 }