diff --git a/Source/v2/Meadow.CLI.Core/DFU/DfuSharp.cs b/Source/v2/Meadow.CLI.Core/DFU/DfuSharp.cs
index e88d813a..13faa55f 100644
--- a/Source/v2/Meadow.CLI.Core/DFU/DfuSharp.cs
+++ b/Source/v2/Meadow.CLI.Core/DFU/DfuSharp.cs
@@ -278,8 +278,8 @@ public class DfuDevice : IDisposable
 
         public DfuDevice(IntPtr device, InterfaceDescriptor interface_descriptor, DfuFunctionDescriptor dfu_descriptor)
         {
-            interface_descriptor = interface_descriptor;
-            dfu_descriptor = dfu_descriptor;
+            this.interface_descriptor = interface_descriptor;
+            this.dfu_descriptor = dfu_descriptor;
 
             if (NativeMethods.libusb_open(device, ref handle) < 0)
             {
@@ -287,12 +287,11 @@ public DfuDevice(IntPtr device, InterfaceDescriptor interface_descriptor, DfuFun
             }
         }
 
-        public event UploadingEventHandler Uploading;
+        public event UploadingEventHandler Uploading = default!;
 
         protected virtual void OnUploading(UploadingEventArgs e)
         {
-            if (Uploading != null)
-                Uploading(this, e);
+            Uploading?.Invoke(this, e);
         }
         public void ClaimInterface()
         {
diff --git a/Source/v2/Meadow.CLI.Core/PackageManager/PackageManager.AssemblyManager.cs b/Source/v2/Meadow.CLI.Core/PackageManager/PackageManager.AssemblyManager.cs
index 2d0c4610..2df69f04 100644
--- a/Source/v2/Meadow.CLI.Core/PackageManager/PackageManager.AssemblyManager.cs
+++ b/Source/v2/Meadow.CLI.Core/PackageManager/PackageManager.AssemblyManager.cs
@@ -6,13 +6,13 @@ public partial class PackageManager
     public const string PostLinkDirectoryName = "postlink_bin";
     public const string PackageOutputDirectoryName = "mpak";
 
-    private string? _meadowAssembliesPath;
+    private string _meadowAssembliesPath = string.Empty;
 
-    private string? MeadowAssembliesPath
+    private string MeadowAssembliesPath
     {
         get
         {
-            if (_meadowAssembliesPath == null)
+            if (string.IsNullOrWhiteSpace(_meadowAssembliesPath))
             {   // for now we only support F7
                 // TODO: add switch and support for other platforms
                 var store = _fileManager.Firmware["Meadow F7"];
diff --git a/Source/v2/Meadow.CLI.Core/PackageManager/PackageManager.BuildOptions.cs b/Source/v2/Meadow.CLI.Core/PackageManager/PackageManager.BuildOptions.cs
index 190f44c8..412c1c5a 100644
--- a/Source/v2/Meadow.CLI.Core/PackageManager/PackageManager.BuildOptions.cs
+++ b/Source/v2/Meadow.CLI.Core/PackageManager/PackageManager.BuildOptions.cs
@@ -12,4 +12,4 @@ public record DeployOptions
             public bool? IncludePDBs { get; set; }
         }
     }
-}
+}
\ No newline at end of file
diff --git a/Source/v2/Meadow.Cli/AppManager.cs b/Source/v2/Meadow.Cli/AppManager.cs
index c52d63d1..edebb7d5 100644
--- a/Source/v2/Meadow.Cli/AppManager.cs
+++ b/Source/v2/Meadow.Cli/AppManager.cs
@@ -32,7 +32,7 @@ public static async Task DeployApplication(
         string localBinaryDirectory,
         bool includePdbs,
         bool includeXmlDocs,
-        ILogger logger,
+        ILogger? logger,
         CancellationToken cancellationToken)
     {
         // TODO: add sub-folder support when HCOM supports it
@@ -43,7 +43,7 @@ public static async Task DeployApplication(
         var dependencies = packageManager.GetDependencies(new FileInfo(Path.Combine(localBinaryDirectory, "App.dll")));
         dependencies.Add(Path.Combine(localBinaryDirectory, "App.dll"));
 
-        logger.LogInformation("Generating the list of files to deploy...");
+        logger?.LogInformation("Generating the list of files to deploy...");
         foreach (var file in dependencies)
         {
             // TODO: add any other filtering capability here
@@ -65,7 +65,7 @@ public static async Task DeployApplication(
 
         if (localFiles.Count() == 0)
         {
-            logger.LogInformation($"No new files to deploy");
+            logger?.LogInformation($"No new files to deploy");
         }
 
         // get a list of files on-device, with CRCs
@@ -85,7 +85,7 @@ public static async Task DeployApplication(
         // delete those files
         foreach (var file in removeFiles)
         {
-            logger.LogInformation($"Deleting file '{file}'...");
+            logger?.LogInformation($"Deleting file '{file}'...");
             await connection.DeleteFile(file, cancellationToken);
         }
 
@@ -94,7 +94,7 @@ public static async Task DeployApplication(
         {
             var existing = deviceFiles.FirstOrDefault(f => Path.GetFileName(f.Name) == Path.GetFileName(localFile.Key));
 
-            if (existing != null)
+            if (existing != null && existing.Crc != null)
             {
                 if (uint.Parse(existing.Crc.Substring(2), System.Globalization.NumberStyles.HexNumber) == localFile.Value)
                 {
@@ -107,7 +107,7 @@ public static async Task DeployApplication(
 
             if (!await connection?.WriteFile(localFile.Key, null, cancellationToken))
             {
-                logger.LogWarning($"Error sending'{Path.GetFileName(localFile.Key)}'.  Retrying.");
+                logger?.LogWarning($"Error sending'{Path.GetFileName(localFile.Key)}'.  Retrying.");
                 await Task.Delay(100);
                 goto send_file;
             }
diff --git a/Source/v2/Meadow.Cli/Commands/Current/App/AppDeployCommand.cs b/Source/v2/Meadow.Cli/Commands/Current/App/AppDeployCommand.cs
index 8ff2b81a..7eee58ae 100644
--- a/Source/v2/Meadow.Cli/Commands/Current/App/AppDeployCommand.cs
+++ b/Source/v2/Meadow.Cli/Commands/Current/App/AppDeployCommand.cs
@@ -92,7 +92,7 @@ protected override async ValueTask ExecuteCommand()
                 file = new FileInfo(path);
             }
 
-            var targetDirectory = file.DirectoryName;
+            var targetDirectory = file.DirectoryName!;
 
             await AppManager.DeployApplication(_packageManager, connection, targetDirectory, true, false, Logger, CancellationToken);
 
diff --git a/Source/v2/Meadow.Cli/Commands/Current/App/AppRunCommand.cs b/Source/v2/Meadow.Cli/Commands/Current/App/AppRunCommand.cs
index 04f997ca..a5542d8d 100644
--- a/Source/v2/Meadow.Cli/Commands/Current/App/AppRunCommand.cs
+++ b/Source/v2/Meadow.Cli/Commands/Current/App/AppRunCommand.cs
@@ -8,7 +8,7 @@ namespace Meadow.CLI.Commands.DeviceManagement;
 public class AppRunCommand : BaseDeviceCommand<AppRunCommand>
 {
     private readonly IPackageManager _packageManager;
-    private string _lastFile;
+    private string? _lastFile;
 
     [CommandOption("no-prefix", 'n', IsRequired = false, Description = "When set, the message source prefix (e.g. 'stdout>') is suppressed during 'listen'")]
     public bool NoPrefix { get; set; }
diff --git a/Source/v2/Meadow.Cli/Commands/Current/Device/DeviceProvisionCommand.cs b/Source/v2/Meadow.Cli/Commands/Current/Device/DeviceProvisionCommand.cs
index 9f155d95..792d9284 100644
--- a/Source/v2/Meadow.Cli/Commands/Current/Device/DeviceProvisionCommand.cs
+++ b/Source/v2/Meadow.Cli/Commands/Current/Device/DeviceProvisionCommand.cs
@@ -44,7 +44,7 @@ protected override async ValueTask ExecuteCommand()
             Logger?.LogInformation("Retrieving your user and organization information...");
 
             var userOrgs = await _userService.GetUserOrgs(Host, CancellationToken).ConfigureAwait(false);
-            if (!userOrgs.Any())
+            if (userOrgs == null || !userOrgs.Any())
             {
                 Logger?.LogInformation($"Please visit {Host} to register your account.");
                 return;
diff --git a/Source/v2/Meadow.Cli/Commands/Current/Firmware/FirmwareDefaultCommand.cs b/Source/v2/Meadow.Cli/Commands/Current/Firmware/FirmwareDefaultCommand.cs
index 978ff994..a0b33ef2 100644
--- a/Source/v2/Meadow.Cli/Commands/Current/Firmware/FirmwareDefaultCommand.cs
+++ b/Source/v2/Meadow.Cli/Commands/Current/Firmware/FirmwareDefaultCommand.cs
@@ -24,7 +24,7 @@ protected override async ValueTask ExecuteCommand()
 
         if (Version == null)
         {
-            Logger?.LogInformation($"Default firmware is '{collection.DefaultPackage.Version}'.");
+            Logger?.LogInformation($"Default firmware is '{collection?.DefaultPackage?.Version}'.");
         }
         else
         {
diff --git a/Source/v2/Meadow.Cli/Commands/Current/Firmware/FirmwareWriteCommand.cs b/Source/v2/Meadow.Cli/Commands/Current/Firmware/FirmwareWriteCommand.cs
index fc220b81..c5b54558 100644
--- a/Source/v2/Meadow.Cli/Commands/Current/Firmware/FirmwareWriteCommand.cs
+++ b/Source/v2/Meadow.Cli/Commands/Current/Firmware/FirmwareWriteCommand.cs
@@ -30,7 +30,6 @@ public class FirmwareWriteCommand : BaseDeviceCommand<FirmwareWriteCommand>
     private ISettingsManager Settings { get; }
 
     private ILibUsbDevice? _libUsbDevice;
-    private bool _fileWriteError = false;
 
     public FirmwareWriteCommand(ISettingsManager settingsManager, FileManager fileManager, MeadowConnectionManager connectionManager, ILoggerFactory loggerFactory)
         : base(connectionManager, loggerFactory)
@@ -201,11 +200,17 @@ private async ValueTask WriteFiles(IMeadowConnection connection, FirmwareType[]
         };
         connection.FileWriteFailed += (s, e) =>
         {
-            _fileWriteError = true;
+            Logger?.LogError("Error writing file");
         };
 
         var package = await GetSelectedPackage();
 
+        if (package == null)
+        {
+            Logger?.LogError($"Firware write failed - unable to find selected package");
+            return;
+        }
+
         var wasRuntimeEnabled = await connection!.Device!.IsRuntimeEnabled(CancellationToken);
 
         if (wasRuntimeEnabled)
@@ -246,7 +251,7 @@ private async ValueTask WriteFiles(IMeadowConnection connection, FirmwareType[]
             return;
         }
 
-        if (FirmwareFileTypes.Contains(FirmwareType.ESP))
+        if (FirmwareFileTypes != null && FirmwareFileTypes.Contains(FirmwareType.ESP))
         {
             Logger?.LogInformation($"{Environment.NewLine}Writing Coprocessor files...");
 
diff --git a/Source/v2/Meadow.Cli/Commands/Current/Port/PortSelectCommand.cs b/Source/v2/Meadow.Cli/Commands/Current/Port/PortSelectCommand.cs
index 6e2e26af..bf740db6 100644
--- a/Source/v2/Meadow.Cli/Commands/Current/Port/PortSelectCommand.cs
+++ b/Source/v2/Meadow.Cli/Commands/Current/Port/PortSelectCommand.cs
@@ -50,6 +50,9 @@ private async Task CallConfigCommand(string selectedPort)
             Settings = new string[] { "route", selectedPort }
         };
 
-        await setCommand.ExecuteAsync(Console);
+        if (Console != null)
+        {
+            await setCommand.ExecuteAsync(Console);
+        }
     }
 }
\ No newline at end of file
diff --git a/Source/v2/Meadow.Cli/Commands/Legacy/FlashOsCommand.cs b/Source/v2/Meadow.Cli/Commands/Legacy/FlashOsCommand.cs
index 7acc1849..57a9578c 100644
--- a/Source/v2/Meadow.Cli/Commands/Legacy/FlashOsCommand.cs
+++ b/Source/v2/Meadow.Cli/Commands/Legacy/FlashOsCommand.cs
@@ -54,6 +54,12 @@ protected override async ValueTask ExecuteCommand()
     {
         var package = await GetSelectedPackage();
 
+        if (package == null)
+        {
+            Logger?.LogError($"Unable to get selected OS package");
+            return;
+        }
+
         var files = new List<FirmwareType>();
         if (!SkipOS) files.Add(FirmwareType.OS);
         if (!SkipEsp) files.Add(FirmwareType.ESP);
@@ -62,7 +68,7 @@ protected override async ValueTask ExecuteCommand()
 
         if (Files == null)
         {
-            Logger.LogInformation($"Writing all firmware for version '{package.Version}'...");
+            Logger?.LogInformation($"Writing all firmware for version '{package.Version}'...");
 
             Files = new FirmwareType[]
                 {
@@ -80,7 +86,7 @@ protected override async ValueTask ExecuteCommand()
 
         bool deviceSupportsOta = false; // TODO: get this based on device OS version
 
-        if (package?.OsWithoutBootloader == null
+        if (package.OsWithoutBootloader == null
             || !deviceSupportsOta
             || UseDfu)
         {
@@ -259,7 +265,14 @@ private async ValueTask WriteFiles()
             Logger?.LogInformation(message);
         };
 
-        var package = await GetSelectedPackage();
+
+        var pack = await GetSelectedPackage();
+
+        if (pack == null)
+        {
+            Logger?.LogError($"Unable to get selected OS package");
+        }
+        FirmwarePackage package = pack!;
 
         var wasRuntimeEnabled = await connection.Device.IsRuntimeEnabled(CancellationToken);
 
@@ -275,7 +288,7 @@ private async ValueTask WriteFiles()
             Console?.Output.Write($"Writing {e.fileName}: {p:0}%     \r");
         };
 
-        if (Files.Contains(FirmwareType.OS))
+        if (Files!.Contains(FirmwareType.OS))
         {
             if (UseDfu)
             {
@@ -288,7 +301,7 @@ private async ValueTask WriteFiles()
                 throw new NotSupportedException("OtA writes for the OS are not yet supported");
             }
         }
-        if (Files.Contains(FirmwareType.Runtime))
+        if (Files!.Contains(FirmwareType.Runtime))
         {
             Logger?.LogInformation($"{Environment.NewLine}Writing Runtime {package.Version}...");
 
@@ -299,7 +312,7 @@ private async ValueTask WriteFiles()
 
             await connection.Device.WriteRuntime(rtpath, CancellationToken);
         }
-        if (Files.Contains(FirmwareType.ESP))
+        if (Files!.Contains(FirmwareType.ESP))
         {
             Logger?.LogInformation($"{Environment.NewLine}Writing Coprocessor files...");
 
@@ -313,8 +326,6 @@ private async ValueTask WriteFiles()
             await connection.Device.WriteCoprocessorFiles(fileList, CancellationToken);
         }
 
-        Logger?.LogInformation($"{Environment.NewLine}");
-
         if (wasRuntimeEnabled)
         {
             await connection.Device.RuntimeEnable();
diff --git a/Source/v2/Meadow.Cloud.Client/Messages/User.cs b/Source/v2/Meadow.Cloud.Client/Messages/User.cs
index 1951d6e6..4c6ac125 100644
--- a/Source/v2/Meadow.Cloud.Client/Messages/User.cs
+++ b/Source/v2/Meadow.Cloud.Client/Messages/User.cs
@@ -7,4 +7,4 @@ public record User
     public string FirstName { get; set; }
     public string LastName { get; set; }
     public string FullName { get; set; }
-}
+}
\ No newline at end of file
diff --git a/Source/v2/Meadow.HCom.Integration.Tests/SerialConnectionTests.cs b/Source/v2/Meadow.HCom.Integration.Tests/SerialConnectionTests.cs
index 92467a24..707a94d0 100644
--- a/Source/v2/Meadow.HCom.Integration.Tests/SerialConnectionTests.cs
+++ b/Source/v2/Meadow.HCom.Integration.Tests/SerialConnectionTests.cs
@@ -16,7 +16,7 @@ public void TestInvalidPortName()
         }
 
         [Fact]
-        public async void TestListen()
+        public void TestListen()
         {
             using (var connection = new SerialConnection(ValidPortName))
             {
diff --git a/Source/v2/Meadow.Hcom/Connections/SerialConnection.cs b/Source/v2/Meadow.Hcom/Connections/SerialConnection.cs
index 698af035..2ca4f621 100644
--- a/Source/v2/Meadow.Hcom/Connections/SerialConnection.cs
+++ b/Source/v2/Meadow.Hcom/Connections/SerialConnection.cs
@@ -16,10 +16,10 @@ public partial class SerialConnection : ConnectionBase, IDisposable
     public const int ReadBufferSizeBytes = 0x2000;
     private const int DefaultTimeout = 5000;
 
-    private event EventHandler<string> FileReadCompleted = delegate { };
-    private event EventHandler FileWriteAccepted;
-    private event EventHandler<string> FileDataReceived;
-    public event ConnectionStateChangedHandler ConnectionStateChanged = delegate { };
+    private event EventHandler<string> FileReadCompleted = default!;
+    private event EventHandler FileWriteAccepted = default!;
+    private event EventHandler<string> FileDataReceived = default!;
+    public event ConnectionStateChangedHandler ConnectionStateChanged = default!;
 
     private readonly SerialPort _port;
     private readonly ILogger? _logger;
@@ -1178,7 +1178,7 @@ public override async Task<string> GetPublicKey(CancellationToken? cancellationT
     {
         var command = RequestBuilder.Build<GetPublicKeyRequest>();
 
-        string? contents = null;
+        string contents = string.Empty;
 
         void OnFileDataReceived(object? sender, string data)
         {
diff --git a/Source/v2/Meadow.Hcom/Connections/TcpConnection.cs b/Source/v2/Meadow.Hcom/Connections/TcpConnection.cs
index a7b3157f..207d6a4f 100644
--- a/Source/v2/Meadow.Hcom/Connections/TcpConnection.cs
+++ b/Source/v2/Meadow.Hcom/Connections/TcpConnection.cs
@@ -5,8 +5,8 @@ namespace Meadow.Hcom;
 
 public class TcpConnection : ConnectionBase
 {
-    private HttpClient _client;
-    private string _baseUri;
+    private readonly HttpClient _client;
+    private readonly string _baseUri;
 
     public override string Name => _baseUri;
 
diff --git a/Source/v2/Meadow.Hcom/SerialRequests/RequestBuilder.cs b/Source/v2/Meadow.Hcom/SerialRequests/RequestBuilder.cs
index 0fac22e8..c20117a2 100644
--- a/Source/v2/Meadow.Hcom/SerialRequests/RequestBuilder.cs
+++ b/Source/v2/Meadow.Hcom/SerialRequests/RequestBuilder.cs
@@ -2,7 +2,7 @@
 {
     public static class RequestBuilder
     {
-        private static uint _sequenceNumber;
+        //private static uint _sequenceNumber;
 
         public static T Build<T>(uint userData = 0, ushort extraData = 0, ushort protocol = Protocol.HCOM_PROTOCOL_HCOM_VERSION_NUMBER)
             where T : Request, new()
diff --git a/Source/v2/Meadow.SoftwareManager/DownloadFileStream.cs b/Source/v2/Meadow.SoftwareManager/DownloadFileStream.cs
index da0f1e66..adad19f6 100644
--- a/Source/v2/Meadow.SoftwareManager/DownloadFileStream.cs
+++ b/Source/v2/Meadow.SoftwareManager/DownloadFileStream.cs
@@ -6,7 +6,7 @@ namespace Meadow.Software;
 
 internal class DownloadFileStream : Stream, IDisposable
 {
-    public event EventHandler<long> DownloadProgress;
+    public event EventHandler<long> DownloadProgress = default!;
 
     private readonly Stream _stream;
 
diff --git a/Source/v2/Meadow.SoftwareManager/F7FirmwarePackageCollection.cs b/Source/v2/Meadow.SoftwareManager/F7FirmwarePackageCollection.cs
index 9d13bed8..ffac2127 100644
--- a/Source/v2/Meadow.SoftwareManager/F7FirmwarePackageCollection.cs
+++ b/Source/v2/Meadow.SoftwareManager/F7FirmwarePackageCollection.cs
@@ -11,13 +11,13 @@ namespace Meadow.Software;
 public class F7FirmwarePackageCollection : IFirmwarePackageCollection
 {
     /// <inheritdoc/>
-    public event EventHandler<long> DownloadProgress;
+    public event EventHandler<long> DownloadProgress = default!;
 
     public event EventHandler<FirmwarePackage?> DefaultVersionChanged;
 
     public string PackageFileRoot { get; }
 
-    private List<FirmwarePackage> _f7Packages = new();
+    private readonly List<FirmwarePackage> _f7Packages = new();
 
     public static string DefaultF7FirmwareStoreRoot = Path.Combine(
         Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
@@ -85,7 +85,7 @@ public Task DeletePackage(string version)
 
         // if we're deleting the default, we need to det another default
         var i = _f7Packages.Count - 1;
-        while (DefaultPackage.Version == _f7Packages[i].Version)
+        while (DefaultPackage?.Version == _f7Packages[i].Version)
         {
             i--;
         }
diff --git a/Source/v2/Meadow.SoftwareManager/FirmwarePackage.cs b/Source/v2/Meadow.SoftwareManager/FirmwarePackage.cs
index ac963c90..339953f9 100644
--- a/Source/v2/Meadow.SoftwareManager/FirmwarePackage.cs
+++ b/Source/v2/Meadow.SoftwareManager/FirmwarePackage.cs
@@ -11,7 +11,7 @@ internal FirmwarePackage(IFirmwarePackageCollection collection)
         _collection = collection;
     }
 
-    public string GetFullyQualifiedPath(string file)
+    public string GetFullyQualifiedPath(string? file)
     {
         return Path.Combine(_collection.PackageFileRoot, Version, file);
     }