diff --git a/Beam.Temporary.Cli/DownloadBuilder.cs b/Beam.Temporary.Cli/DownloadBuilder.cs
index 87cb95e..5b30139 100644
--- a/Beam.Temporary.Cli/DownloadBuilder.cs
+++ b/Beam.Temporary.Cli/DownloadBuilder.cs
@@ -42,6 +42,9 @@ namespace Beam.Temporary.Cli {
 
         public interface IAlternativeTransformStage {
             IContextStage WithTransformer(AsyncTransformer<RawType, OutType> transformer);
+            IContextStage WithTransformer(Func<RawType, OutType> transformer) {
+                return WithTransformer(rt => Task.FromResult(transformer(rt)));
+            }
         }
 
         public interface IContextStage {
@@ -192,8 +195,8 @@ namespace Beam.Temporary.Cli {
                             _parallelism,
                             context.DownloadLogger),
                     // ────────────────  fragmented binary  ────────────────
-                    (true, AsyncTransformer<byte[], OutType> asyncBinaryTransformer,
-                    AsyncDownloadFailurePredicate<byte[]>[] responseFailurePredicates)
+                    (true, AsyncTransformer<ByteDocument, OutType> asyncBinaryTransformer,
+                    AsyncDownloadFailurePredicate<ByteDocument>[] responseFailurePredicates)
                         => new UnitFragmentDownloaderBinary<OutType>(
                             context.Client,
                             asyncBinaryTransformer,
@@ -208,8 +211,8 @@ namespace Beam.Temporary.Cli {
                             asyncHtmlTransformer,
                             documentFailurePredicates),
                     // ────────────────  single binary  ────────────────
-                    (false, AsyncTransformer<byte[], OutType> asyncBinaryTransformer,
-                    AsyncDownloadFailurePredicate<byte[]>[] responseFailurePredicates)
+                    (false, AsyncTransformer<ByteDocument, OutType> asyncBinaryTransformer,
+                    AsyncDownloadFailurePredicate<ByteDocument>[] responseFailurePredicates)
                         => new UnitDownloaderBinary<OutType>(
                             context.Client,
                             asyncBinaryTransformer,
diff --git a/Beam/ByteDocument.cs b/Beam/ByteDocument.cs
index 7a6cdfe..fa2d047 100644
--- a/Beam/ByteDocument.cs
+++ b/Beam/ByteDocument.cs
@@ -1,7 +1,7 @@
 using System.Text;
 
 namespace Beam {
-    internal class ByteDocument(string filename, byte[] content, Encoding? encoding = null) : Document(filename, encoding) {
+    public class ByteDocument(string filename, byte[] content, Encoding? encoding = null) : Document(filename, encoding) {
         public byte[] Content { get; set; } = content;
 
         public override byte[] ToBytes() {
diff --git a/Beam/SequentialDownloader.cs b/Beam/SequentialDownloader.cs
index d2a9171..f4b5d1b 100644
--- a/Beam/SequentialDownloader.cs
+++ b/Beam/SequentialDownloader.cs
@@ -16,7 +16,13 @@ namespace Beam {
             Context = context;
             Logger = logger;
             LinksEnumerator = Context.Links.GetEnumerator();
-            LinksEnumerator.Reset();
+
+            try {
+                LinksEnumerator.Reset();
+            } catch (NotSupportedException) {
+                Logger?.LogWarning("Enumerator of type {} does not support resets. This may cause buggy behavior", LinksEnumerator.GetType());
+            }
+
             if (!LinksEnumerator.MoveNext())
                 throw new ArgumentOutOfRangeException(S.M.LinksCannotBeEmpty);
             Current = default(OutType);
@@ -29,14 +35,20 @@ namespace Beam {
         }
 
         public async ValueTask<bool> MoveNextAsync() {
+            if (!LinksEnumerator.Current.HasValue)
+                return false;
+
+            //Logger?.LogInformation("MoveNextAsync()");
             var unit = GetUnitDownloader(); // safe to instantiate per request.
             var idealLinkCount = unit.LinksPerDownload;
             List<Ordered<string>> links = [];
-            
+
+            //Logger?.LogInformation("MoveNextAsync() \n\t -> Links.Current = {} ", LinksEnumerator.Current.Link.AbsoluteUri);
             links.Add(new Ordered<string>(LinksEnumerator.Current.Link.ToString(), LastOrder++));
 
             while (LinksEnumerator.MoveNext() && LinksEnumerator.Current != SourceLink.InvalidLink && links.Count < idealLinkCount)
                 links.Add(new Ordered<string>(LinksEnumerator.Current.Link.ToString(), LastOrder++));
+            //Logger?.LogInformation("MoveNextAsync() \n\t -> links.Count = {} ", links.Count);
             if (links.Count == 0) {
                 Logger?.LogInformation("Out of links!");
                 return false;
diff --git a/Beam/SourceLink.cs b/Beam/SourceLink.cs
index 721b442..c1a5e9d 100644
--- a/Beam/SourceLink.cs
+++ b/Beam/SourceLink.cs
@@ -14,10 +14,16 @@ namespace Beam {
         public static SourceLink InvalidLink { get; } = new("invalid://link");
 
         public static bool operator ==(SourceLink lhs, SourceLink rhs) {
-            return lhs.Link == rhs.Link; 
+            if (lhs.HasValue && rhs.HasValue)
+                return lhs.Link == rhs.Link;
+            else
+                return lhs.Link_ == rhs.Link_;
         }
         public static bool operator !=(SourceLink lhs, SourceLink rhs) {
-            return lhs.Link != rhs.Link;
+            if (lhs.HasValue && rhs.HasValue)
+                return lhs.Link != rhs.Link;
+            else
+                return lhs.Link_ != rhs.Link_;
         }
 
         public override bool Equals(object? obj) {
diff --git a/Beam/UnitDownloaderBinary.cs b/Beam/UnitDownloaderBinary.cs
index 375aecc..8d45471 100644
--- a/Beam/UnitDownloaderBinary.cs
+++ b/Beam/UnitDownloaderBinary.cs
@@ -10,12 +10,12 @@ namespace Beam {
     /// </summary>
     public class UnitDownloaderBinary<T>(
         HttpClient client,
-        AsyncTransformer<byte[], T> transformer,
-        AsyncDownloadFailurePredicate<byte[]>?[]? failurePredicates = null)
+        AsyncTransformer<ByteDocument, T> transformer,
+        AsyncDownloadFailurePredicate<ByteDocument>?[]? failurePredicates = null)
         : IUnitDownloader<T> {
         public HttpClient Client { get; } = client;
-        public virtual AsyncTransformer<byte[], T> Transformer { get; } = transformer;
-        public virtual AsyncDownloadFailurePredicate<byte[]>?[]? FailurePredicates { get; } = failurePredicates;
+        public virtual AsyncTransformer<ByteDocument, T> Transformer { get; } = transformer;
+        public virtual AsyncDownloadFailurePredicate<ByteDocument>?[]? FailurePredicates { get; } = failurePredicates;
 
         public int LinksPerDownload { get; } = 1;
 
@@ -26,7 +26,8 @@ namespace Beam {
             var failed = false;
             await Parallel.ForEachAsync(FailurePredicates, async (pred, ct) => {
                 if (failed || pred is null) return;
-                if (await pred(await response.Content.ReadAsByteArrayAsync(ct))) failed = true;
+                if (await pred(new ByteDocument(response.RequestMessage?.RequestUri?.AbsolutePath ?? "", await response.Content.ReadAsByteArrayAsync(ct))))
+                    failed = true;
             });
             return failed;
         }
@@ -40,7 +41,7 @@ namespace Beam {
                 if (await IsFailure(response)) return (false, default);
 
                 var bytes = await response.Content.ReadAsByteArrayAsync(ct);
-                return (true, await Transformer(bytes));
+                return (true, await Transformer(new ByteDocument(link, bytes)));
             } catch {
                 return (false, default);
             }
diff --git a/Beam/UnitFragmentDownloaderBinary.cs b/Beam/UnitFragmentDownloaderBinary.cs
index c3ad884..7c5a342 100644
--- a/Beam/UnitFragmentDownloaderBinary.cs
+++ b/Beam/UnitFragmentDownloaderBinary.cs
@@ -12,8 +12,8 @@ namespace Beam {
     public class UnitFragmentDownloaderBinary<T>
         : IUnitDownloader<Fragment<Ordered<T>>> {
         public UnitFragmentDownloaderBinary(HttpClient client,
-                                            AsyncTransformer<byte[], T> transformer,
-                                            AsyncDownloadFailurePredicate<byte[]>?[]? failurePredicate = null,
+                                            AsyncTransformer<ByteDocument, T> transformer,
+                                            AsyncDownloadFailurePredicate<ByteDocument>?[]? failurePredicate = null,
                                             int fragmentSize = 4,
                                             ILogger? logger = null,
                                             IUnitDownloader<T>? internalDownloader = null) {
@@ -27,8 +27,8 @@ namespace Beam {
         }
 
         public HttpClient Client { get; }
-        public AsyncTransformer<byte[], T> Transformer { get; }
-        public AsyncDownloadFailurePredicate<byte[]>?[]? FailurePredicate { get; }
+        public AsyncTransformer<ByteDocument, T> Transformer { get; }
+        public AsyncDownloadFailurePredicate<ByteDocument>?[]? FailurePredicate { get; }
         public int LinksPerDownload { get; set; }
         public ILogger? Logger { get; set; }
 
diff --git a/aeqw89.Beam/aeqw89.Beam.csproj b/aeqw89.Beam/aeqw89.Beam.csproj
index 2b89c7c..69f6b5e 100644
--- a/aeqw89.Beam/aeqw89.Beam.csproj
+++ b/aeqw89.Beam/aeqw89.Beam.csproj
@@ -7,7 +7,7 @@
         <Title>Beam</Title>
         <Authors>aeqw89</Authors>
         <Company>qwsdcvghyu</Company>
-        <Version>1.2.4</Version>
+        <Version>1.2.10</Version>
         <Description>A library for downloading internet resources</Description>
         <PackageProjectUrl>https://github.com/qwsdcvghyu89/Beam</PackageProjectUrl>
         <RepositoryUrl>https://github.com/qwsdcvghyu89/Beam</RepositoryUrl>