diff --git a/Netch/Models/ParameterBase.cs b/Netch/Models/ParameterBase.cs
index 4ecbb2a5..52d2e06f 100644
--- a/Netch/Models/ParameterBase.cs
+++ b/Netch/Models/ParameterBase.cs
@@ -1,7 +1,6 @@
 using System;
 using System.Linq;
 using System.Reflection;
-using Netch.Utils;
 
 namespace Netch.Models
 {
@@ -49,7 +48,7 @@ namespace Netch.Models
                 case bool b:
                     return b ? $"{prefix}{key}" : null;
                 default:
-                    if ((value?.ToString() ?? null).IsNullOrWhiteSpace())
+                    if (string.IsNullOrWhiteSpace(value?.ToString()))
                         return p.IsDefined(typeof(OptionalAttribute)) ? null : throw new RequiredArgumentValueInvalidException(p.Name, this, null);
 
                     if (p.IsDefined(typeof(QuoteAttribute)))
diff --git a/Netch/Utils/Utils.cs b/Netch/Utils/Utils.cs
index 2d4e0f97..4f817238 100644
--- a/Netch/Utils/Utils.cs
+++ b/Netch/Utils/Utils.cs
@@ -106,7 +106,7 @@ namespace Netch.Utils
             {
                 var sha256 = SHA256.Create();
                 using var fileStream = File.OpenRead(filePath);
-                return sha256.ComputeHash(fileStream).Aggregate(string.Empty, (current, b) => current + b.ToString("x2"));
+                return string.Concat(sha256.ComputeHash(fileStream).Select(b => b.ToString("x2")));
             }
             catch
             {