diff --git a/Binary/Sources/Deli/Error/PropertyParserError.swift b/Binary/Sources/Deli/Error/PropertyParserError.swift
index cc734ed..3dcb01b 100644
--- a/Binary/Sources/Deli/Error/PropertyParserError.swift
+++ b/Binary/Sources/Deli/Error/PropertyParserError.swift
@@ -5,7 +5,6 @@
 
 enum PropertyParserError: Error {
     case propertyNotFound
-    case propertyIsNotString
     case pathNotFound
 
     case notStartedBracket
@@ -18,8 +17,6 @@ enum PropertyParserError: Error {
         switch self {
         case .propertyNotFound:
             return "Property not found in configuration property."
-        case .propertyIsNotString:
-            return "Property is not string value."
         case .pathNotFound:
             return "Path not found in configuration property."
         case .notStartedBracket:
diff --git a/Binary/Sources/Deli/Runner/Corrector/ConfigPropertyCorrector.swift b/Binary/Sources/Deli/Runner/Corrector/ConfigPropertyCorrector.swift
index 44c57a9..4d4025f 100644
--- a/Binary/Sources/Deli/Runner/Corrector/ConfigPropertyCorrector.swift
+++ b/Binary/Sources/Deli/Runner/Corrector/ConfigPropertyCorrector.swift
@@ -3,6 +3,8 @@
 //  Deli
 //
 
+import Foundation
+
 final class ConfigPropertyCorrector: Correctable {
 
     // MARK: - Private
@@ -23,11 +25,11 @@ final class ConfigPropertyCorrector: Correctable {
                     Logger.log(.error("Not found configuration property: \(path)", info.structure.getSourceLine(with: info.content)))
                     throw CorrectorError.notFoundConfigurationProperty
                 }
-                guard let safeProperty = property as? String else {
-                    Logger.log(.error("Not found configuration property: \(path)", info.structure.getSourceLine(with: info.content)))
-                    throw CorrectorError.notFoundConfigurationProperty
+                if property is NSNull {
+                    return ""
+                } else {
+                    return "\(property)"
                 }
-                return safeProperty
             }
 
             return result
diff --git a/Binary/Sources/Deli/Runner/Corrector/QualifierByCorrector.swift b/Binary/Sources/Deli/Runner/Corrector/QualifierByCorrector.swift
index 9cc5e7c..51d6ee8 100644
--- a/Binary/Sources/Deli/Runner/Corrector/QualifierByCorrector.swift
+++ b/Binary/Sources/Deli/Runner/Corrector/QualifierByCorrector.swift
@@ -3,6 +3,8 @@
 //  Deli
 //
 
+import Foundation
+
 final class QualifierByCorrector: Correctable {
 
     // MARK: - Private
@@ -19,11 +21,11 @@ final class QualifierByCorrector: Correctable {
                 Logger.log(.error("Property not found in configuration property(\(qualifierBy))", info.structure.getSourceLine(with: info.content)))
                 throw PropertyParserError.propertyNotFound
             }
-            guard let safeProperty = property as? String else {
-                Logger.log(.error("Property is not string value(\(qualifierBy))", info.structure.getSourceLine(with: info.content)))
-                throw PropertyParserError.propertyIsNotString
+            if property is NSNull {
+                dependency.qualifier = ""
+            } else {
+                dependency.qualifier = "\(property)"
             }
-            dependency.qualifier = safeProperty
         } catch {
             Logger.log(.error("Path not found in configuration property(\(qualifierBy))", info.structure.getSourceLine(with: info.content)))
             throw PropertyParserError.pathNotFound
diff --git a/Binary/Sources/Deli/Runner/Generator/SourceGenerator.swift b/Binary/Sources/Deli/Runner/Generator/SourceGenerator.swift
index 423b6ec..b114c3e 100644
--- a/Binary/Sources/Deli/Runner/Generator/SourceGenerator.swift
+++ b/Binary/Sources/Deli/Runner/Generator/SourceGenerator.swift
@@ -44,7 +44,11 @@ final class SourceGenerator: Generator {
             }
             result += "\(indent)]"
         } else {
-            result += "\"\(target)\""
+            if target is NSNull {
+                result += "\"\""
+            } else {
+                result += "\"\(target)\""
+            }
         }
         return result
     }
diff --git a/Binary/Sources/Deli/Runner/Validator/InjectPropertyValidator.swift b/Binary/Sources/Deli/Runner/Validator/InjectPropertyValidator.swift
index e7b011d..bd93780 100644
--- a/Binary/Sources/Deli/Runner/Validator/InjectPropertyValidator.swift
+++ b/Binary/Sources/Deli/Runner/Validator/InjectPropertyValidator.swift
@@ -18,11 +18,7 @@ final class InjectPropertyValidator: Validatable {
             guard let info = parser.inheritanceList(result.instanceType).first else { continue }
 
             for path in propertyResult.propertyKeys {
-                guard let property = try propertyParser.getProperty(path) else {
-                    Logger.log(.error("Not found configuration property: \(path)", info.structure.getSourceLine(with: info.content)))
-                    throw CorrectorError.notFoundConfigurationProperty
-                }
-                if property as? String == nil {
+                guard try propertyParser.getProperty(path) != nil else {
                     Logger.log(.error("Not found configuration property: \(path)", info.structure.getSourceLine(with: info.content)))
                     throw CorrectorError.notFoundConfigurationProperty
                 }