GoLang to build smaller executable file

Normally the executable file built with go is a bit large, it is always desired that a smaller executable file should be generated though. In this post, a couple of ways to reduce the size of the executable will be introduced. The end effect is that the executable file size would be much less than the normal generated one.

The file which is built normally has below size.

Mode                LastWriteTime         Length Name
----                -------------         ------ ----
-a----       12/14/2019   9:47 AM        1974272 main-ori.exe

Add build flags

 Two ld parameters can be added when using go tool to build the project, they are -s and -w.

go build -ldflags="-s -w" main.go

-s: Omit the symbol table and debug information. They are not needed in a production environment in most of cases.

-w: Omit the DWARF information.

These two parameters don't affect the execution of the program but it will reduce the executable file size.

Mode                LastWriteTime         Length Name
----                -------------         ------ ----
-a----       12/14/2019   9:48 AM        1427968 main-flag.exe

UPX compression

upx a tool for binary compression. It can be used to compress binary file and can reduce file size further.

The command to compress the file is:

upx main.exe

After compression, the file size becomes much smaller.

Mode                LastWriteTime         Length Name
----                -------------         ------ ----
-a----       12/14/2019   9:52 AM         495616 main.exe

Happy coding.