Why packed xll is smaller than dll with `PublishSingleFile`

[PaleNeutron]

Here is my output dir:

Mode                 LastWriteTime         Length Name
----                 -------------         ------ ----
d-----         2025/9/19     15:27                publish
-a----         2025/9/19     15:27            311 AmWPSAddin.dna
-a----         2025/9/19     15:27         733184 AmWPSAddin.xll                  
-a----         2025/9/19     15:27            311 AmWPSAddin64.dna
-a----         2025/9/19     15:27         658944 AmWPSAddin64.xll  <------ Much smaller
-a----         2025/9/19     15:27        2502656 AmWPSAddinXll.dll  <------- Much bigger
-a----         2025/9/19     15:27         441256 AmWPSAddinXll.pdb
-a----         2024/5/21     15:07          26112 GraphQL.Client.Abstractions.dll
-a----         2024/5/21     15:07          19456 GraphQL.Client.Abstractions.Websocket.dll
-a----         2024/5/21     15:07          82432 GraphQL.Client.dll
-a----         2024/5/21     15:07          22016 GraphQL.Client.Serializer.Newtonsoft.dll
-a----         2024/5/21     15:06          24576 GraphQL.Primitives.dll
-a----         2025/9/16     16:04         721320 Newtonsoft.Json.dll
-a----         2025/5/19      5:22         164864 Serilog.dll
-a----         2025/4/28      8:38          38912 Serilog.Sinks.File.dll
-a----         2020/2/19     18:05          20856 System.Buffers.dll
-a----         2024/3/20      3:38         189104 System.Diagnostics.DiagnosticSource.dll
-a----          2022/5/8     11:31         142240 System.Memory.dll
-a----         2018/10/5     10:36          72192 System.Net.WebSockets.Client.Managed.dll
-a----         2018/5/15     21:29         115856 System.Numerics.Vectors.dll
-a----         2023/5/19     13:42        1358928 System.Reactive.dll
-a----        2021/10/23      7:40          18024 System.Runtime.CompilerServices.Unsafe.dll
-a----        2023/10/31     23:09          74000 System.Threading.Channels.dll
-a----         2020/2/19     18:05          25984 System.Threading.Tasks.Extensions.dll

I tried to use dotnet PublishSingleFile feature to contains all depends lib in one dll and than pack it into xll. But I found that it seems compiled in incorrect order

1. generate small dll
2. exceldna pack a small xll
3. dotnet generate a big dll

Here is my project file:

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFramework>net472</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <UseWindowsForms>true</UseWindowsForms>
    <PublishSingleFile>true</PublishSingleFile>
    <SelfContained>false</SelfContained>
    <LangVersion>10.0</LangVersion>
  </PropertyGroup>

  <PropertyGroup>
    <ExcelAddInFileName>AmWPSAddin</ExcelAddInFileName>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="ExcelDna.AddIn" Version="1.9.0" />
    <PackageReference Include="ExcelDna.Integration" Version="1.9.0" />
    <PackageReference Include="ExcelDna.Interop" Version="15.0.1" />
    <PackageReference Include="GraphQL.Client" Version="6.1.0" />
    <PackageReference Include="GraphQL.Client.Serializer.Newtonsoft" Version="6.1.0" />
    <PackageReference Include="Newtonsoft.Json" Version="13.0.4" />
    <PackageReference Include="Serilog" Version="4.3.0" />
    <PackageReference Include="Serilog.Sinks.File" Version="7.0.0" />
    <PackageReference Include="System.Net.Http" Version="4.3.4" />
  </ItemGroup>

  <ItemGroup>
    <EmbeddedResource Include="data_dict/*.json" />
  </ItemGroup>
</Project>

[govert]

The packed .xll files are under the "publish" directory. The .xll files in the Output directory that you show does not have the packed contents yet - they won't run without the other bits from this directory.

[PaleNeutron]

@govert The packaged xll in publish directory is nearly the same size of the out one. Currently the correct way to make it a really packed file is define all depends dlls in project_name.dna file. But if I remove the dna file, it will looks like

AmWPSAddin64-packed.xll ≈ AmWPSAddin64.xll < AmWPSAddin64.dll

[govert]

• See the build output to see exactly what gets packed - it's logged in detail.
• If you have a hand-edited .dna file in the project directory, then only the ExternalLibrary and Reference tags with Pack=true will specify assemblies to get packed. You can add more <Reference Path="..." Pack="true" /> tags to pack more libraries
• If you don't have a .dna file in your project, then the Excel-DNA build will create one. It will set up the main library output top get packed.
  • When targeting .NET core, it will use the .deps.json file to decide what else must get packed.
  • When targeting .NET Framework (as you are), you can add additional references to be packed by setting a project property like this

    <!-- Semicolon separated references list to include in .dna. -->
    <!-- Default value: empty -->
    <ExcelAddInInclude></ExcelAddInInclude>
    

    You can generate the include list from all the .dll files in the output directory like this

        <ItemGroup>
          <References Include="$(OutDir)*.dll" Exclude="$(OutDir)$(TargetFileName)"/>
        </ItemGroup>
        <PropertyGroup>
          <ExcelAddInInclude>@(References)</ExcelAddInInclude>
        </PropertyGroup>
      </Target>