diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0345f4df3..a0d7d3c20 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@
   brackets `{{%table}}` (@batyrmastyr)
 - Enh #1145, #1148: Explicitly import classes, functions, and constants in "use" section (@mspirkov)
 - Enh #1148: Add `declare(strict_types=1)` to `Yiisoft\Db\Constant\ColumnInfoSource` (@mspirkov)
+- Enh #1158: Explicitly mark readonly properties (@vjik)
 - Enh #1156: Remove unnecessary files from Composer package (@mspirkov)
 
 ## 2.0.0 December 05, 2025
diff --git a/src/Cache/SchemaCache.php b/src/Cache/SchemaCache.php
index 0a084131f..72b79e46f 100644
--- a/src/Cache/SchemaCache.php
+++ b/src/Cache/SchemaCache.php
@@ -42,7 +42,9 @@ final class SchemaCache
      *
      * @link https://www.php-fig.org/psr/psr-16/
      */
-    public function __construct(private CacheInterface $psrCache) {}
+    public function __construct(
+        private readonly CacheInterface $psrCache,
+    ) {}
 
     /**
      * Remove a value with the specified key from cache.
diff --git a/src/Command/AbstractCommand.php b/src/Command/AbstractCommand.php
index 84cf33dca..c96c6e9d9 100644
--- a/src/Command/AbstractCommand.php
+++ b/src/Command/AbstractCommand.php
@@ -28,7 +28,7 @@
 /**
  * Represents an SQL statement to execute in a database.
  *
- * It's usually created by calling {@see \Yiisoft\Db\Connection\ConnectionInterface::createCommand()}.
+ * It's usually created by calling {@see ConnectionInterface::createCommand()}.
  *
  * You can get the SQL statement it represents via the {@see getSql()} method.
  *
diff --git a/src/Driver/Pdo/AbstractPdoTransaction.php b/src/Driver/Pdo/AbstractPdoTransaction.php
index 53b79fae8..02bbb3799 100644
--- a/src/Driver/Pdo/AbstractPdoTransaction.php
+++ b/src/Driver/Pdo/AbstractPdoTransaction.php
@@ -8,6 +8,7 @@
 use Psr\Log\LoggerAwareTrait;
 use Psr\Log\LogLevel;
 use Throwable;
+use Yiisoft\Db\Connection\ConnectionInterface;
 use Yiisoft\Db\Exception\Exception;
 use Yiisoft\Db\Exception\InvalidConfigException;
 use Yiisoft\Db\Exception\NotSupportedException;
@@ -18,7 +19,7 @@
  *
  * A transaction is a set of SQL statements that must either all succeed or all fail.
  *
- * It's usually created by calling {@see \Yiisoft\Db\Connection\AbstractConnectionAbstractConnection::beginTransaction()}.
+ * It's usually created by calling {@see ConnectionInterface::beginTransaction()}.
  *
  * The following code is a typical example of using transactions (note that some DBMS may not support transactions):
  *
diff --git a/src/Exception/ConvertException.php b/src/Exception/ConvertException.php
index e64271c25..b4d00fe64 100644
--- a/src/Exception/ConvertException.php
+++ b/src/Exception/ConvertException.php
@@ -20,7 +20,10 @@ final class ConvertException
     private const MGS_INTEGRITY_EXCEPTION_2 = 'ORA-00001: unique constraint';
     private const MSG_INTEGRITY_EXCEPTION_3 = 'SQLSTATE[HY';
 
-    public function __construct(private \Exception $e, private string $rawSql) {}
+    public function __construct(
+        private readonly \Exception $e,
+        private readonly string $rawSql,
+    ) {}
 
     /**
      * Converts an exception into a more specific one.
diff --git a/src/Profiler/Context/AbstractContext.php b/src/Profiler/Context/AbstractContext.php
index 048bf7f96..53230f0d4 100644
--- a/src/Profiler/Context/AbstractContext.php
+++ b/src/Profiler/Context/AbstractContext.php
@@ -14,7 +14,9 @@ abstract class AbstractContext implements ContextInterface
 
     private ?Throwable $exception = null;
 
-    public function __construct(private string $method) {}
+    public function __construct(
+        private readonly string $method,
+    ) {}
 
     public function setException(Throwable $e): static
     {
diff --git a/src/Profiler/Context/CommandContext.php b/src/Profiler/Context/CommandContext.php
index b5e4a9cb3..dcd16b0dd 100644
--- a/src/Profiler/Context/CommandContext.php
+++ b/src/Profiler/Context/CommandContext.php
@@ -11,10 +11,10 @@ final class CommandContext extends AbstractContext
     private const PARAMS = 'params';
 
     public function __construct(
-        private string $method,
-        private string $logContext,
-        private string $sql,
-        private array $params,
+        private readonly string $method,
+        private readonly string $logContext,
+        private readonly string $sql,
+        private readonly array $params,
     ) {
         parent::__construct($this->method);
     }
diff --git a/src/Profiler/ProfilerInterface.php b/src/Profiler/ProfilerInterface.php
index c55188086..56936485e 100644
--- a/src/Profiler/ProfilerInterface.php
+++ b/src/Profiler/ProfilerInterface.php
@@ -7,7 +7,7 @@
 /**
  * Interface-decorator to work with `yiisoft\profiler` or another profiler.
  *
- * @see \Yiisoft\Db\Profiler\ProfilerAwareInterface::setProfiler()
+ * @see ProfilerAwareInterface::setProfiler()
  */
 interface ProfilerInterface
 {
diff --git a/src/Query/QueryExpressionBuilder.php b/src/Query/QueryExpressionBuilder.php
index 91734e7b2..209c5d84a 100644
--- a/src/Query/QueryExpressionBuilder.php
+++ b/src/Query/QueryExpressionBuilder.php
@@ -21,7 +21,9 @@
  */
 final class QueryExpressionBuilder implements ExpressionBuilderInterface
 {
-    public function __construct(private QueryBuilderInterface $queryBuilder) {}
+    public function __construct(
+        private readonly QueryBuilderInterface $queryBuilder,
+    ) {}
 
     /**
      * @param QueryInterface $expression
diff --git a/src/QueryBuilder/AbstractDQLQueryBuilder.php b/src/QueryBuilder/AbstractDQLQueryBuilder.php
index 3eae9b427..d55c7a624 100644
--- a/src/QueryBuilder/AbstractDQLQueryBuilder.php
+++ b/src/QueryBuilder/AbstractDQLQueryBuilder.php
@@ -113,7 +113,7 @@ abstract class AbstractDQLQueryBuilder implements DQLQueryBuilderInterface
 
     public function __construct(
         protected QueryBuilderInterface $queryBuilder,
-        private QuoterInterface $quoter,
+        private readonly QuoterInterface $quoter,
     ) {
         $this->expressionBuilders = $this->defaultExpressionBuilders();
         $this->conditionClasses = $this->defaultConditionClasses();
diff --git a/src/QueryBuilder/AbstractQueryBuilder.php b/src/QueryBuilder/AbstractQueryBuilder.php
index 34db88f17..2d7082ef3 100644
--- a/src/QueryBuilder/AbstractQueryBuilder.php
+++ b/src/QueryBuilder/AbstractQueryBuilder.php
@@ -77,11 +77,11 @@ abstract class AbstractQueryBuilder implements QueryBuilderInterface
     protected array $typeMap = [];
 
     public function __construct(
-        private ConnectionInterface $db,
-        private AbstractDDLQueryBuilder $ddlBuilder,
+        private readonly ConnectionInterface $db,
+        private readonly AbstractDDLQueryBuilder $ddlBuilder,
         private AbstractDMLQueryBuilder $dmlBuilder,
-        private AbstractDQLQueryBuilder $dqlBuilder,
-        private AbstractColumnDefinitionBuilder $columnDefinitionBuilder,
+        private readonly AbstractDQLQueryBuilder $dqlBuilder,
+        private readonly AbstractColumnDefinitionBuilder $columnDefinitionBuilder,
     ) {}
 
     public function addCheck(string $table, string $name, string $expression): string
diff --git a/src/Schema/AbstractSchema.php b/src/Schema/AbstractSchema.php
index 64c0727d3..87cbe76a7 100644
--- a/src/Schema/AbstractSchema.php
+++ b/src/Schema/AbstractSchema.php
@@ -53,7 +53,10 @@ abstract class AbstractSchema implements SchemaInterface
     /** @var (Check[]|DefaultValue[]|ForeignKey[]|Index|Index[]|TableSchemaInterface|null)[][] */
     private array $tableMetadata = [];
 
-    public function __construct(protected ConnectionInterface $db, private SchemaCache $schemaCache) {}
+    public function __construct(
+        protected ConnectionInterface $db,
+        private readonly SchemaCache $schemaCache,
+    ) {}
 
     public function getDefaultSchema(): string
     {
diff --git a/src/Schema/Quoter.php b/src/Schema/Quoter.php
index f1bf78367..b25d24a52 100644
--- a/src/Schema/Quoter.php
+++ b/src/Schema/Quoter.php
@@ -38,9 +38,9 @@ class Quoter implements QuoterInterface
 {
     public function __construct(
         /** @psalm-var string[]|string */
-        private array|string $columnQuoteCharacter,
+        private readonly array|string $columnQuoteCharacter,
         /** @psalm-var string[]|string */
-        private array|string $tableQuoteCharacter,
+        private readonly array|string $tableQuoteCharacter,
         private string $tablePrefix = '',
     ) {}