Commandline paramaters for build

Can i somehow use commandline parameters for build installer to set some variables?

write a text file
for example temp.txt wich contains:
!define DEF 1

and include your script file
!include temp.txt

Or pass the /D switch to makensis.

makensis.exe /Dsomething=1 /Dboo script.nsi

Heres an example of the command line I use to build an installer via a batch file

makensis /DBUILDFLAG=%C% /DVERSION=%V% /DREVISION=%R% "InstallerScript.nsi"

Within the script the /D values are referenced with:

${BUILDFLAG}
${VERSION}
${REVISION}