Starting with tcl/tk 8.7 it is possible to build zip based executables with core tcl commands.
To simplify this task a shell script is provided.

&|Version|20200911|&
&|Sources|https://sourceforge.net/projects/kbskit/files/zipkit/20200914/zipkit.sh%|%zipkit.sh%|%|&
&|Builds|https://sourceforge.net/projects/kbskit/files/zipkit/|&
&|Documentation|https://sourceforge.net/projects/kbskit/files/zipkit/20200914/README.md%|%README.md%|%|&
&|Author|[René Zaumseil]|&
&|License|BSD|&

The list of supported packages can be found with:
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zipkit.sh info
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To get all package sources use:
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zipkit.sh sources ?package ..?
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To compile packages or build executables or plain zip files use (macos is not tested!):
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zipkit.sh win|unix|macos ?--* ..? ?tclsh|wish|zip name? ?package ..?
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[MHo] 2020-12-15: What about Windows? No .sh Skripts there.

[RZ] I use msys/mingw. Try p.e. the following bat file:
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:: https://sourceforge.net/projects/mingw-w64/files/Toolchains%20targetting%20Win32/Personal%20Builds/mingw-builds/6.3.0/threads-win32/sjlj/i686-6.3.0-release-win32-sjlj-rt_v5-rev1.7z
:: https://sourceforge.net/projects/mingwbuilds/files/external-binary-packages/msys+7za+wget+svn+git+mercurial+cvs-rev13.7z
:: External programs
set CMD_ZIP1="C:\Programme\WinZip\wzunzip.exe"
set CMD_ZIP2="C:\Programme\7-zip\7z.exe"
set VOL=D:
set DIR=%~dp0
echo === Install mingw/msys system ...
call :_UNZIP %VOL% mingw32 %DIR%\i686-6.3.0-release-win32-sjlj-rt_v5-rev1.7z
call :_UNZIP %VOL%\mingw32 msys %DIR%\msys+7za+wget+svn+git+mercurial+cvs-rev13.7z
echo %VOL%/mingw32 /mingw > %VOL%\mingw32\msys\etc\fstab
echo === Create tclsh/wish binaries ...
%VOL%\mingw32\msys\bin\sh.exe --login %DIR%\zipkit.sh <here come your args>
echo === Done
pause
exit /B 0
:: call :_UNZIP targetdir zipdir zipfile
:_UNZIP
  if not exist "%1\%2" (
    if exist %CMD_ZIP1% (
      echo %CMD_ZIP1% -d %3 %1
      %CMD_ZIP1% -d %3 %1 > nul
    )
  )
  if not exist "%1\%2" (
    if exist %CMD_ZIP2% (
      echo %CMD_ZIP2% x %3 -o%1
      %CMD_ZIP2% x %3 -o%1 > nul
    )
  )
  if not exist "%1\%2" (
    echo ABORT Missing unzip dir "%1\%2"
    pause
    exit
  )
  echo --- Unzip %1\%2 OK
exit /B 0
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