gjs: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/gjs - from package: gjs

You may install the required package with command apt-get install {package}

Error in other languages:
gjs: bevel nie gevind nie
gjs: comandă negăsită
gjs: comando não encontrado
gjs: commande introuvable
gjs: command not found
gjs: käsku ei ole
gjs: không tìm thấy lệnh
gjs: komanda nerasta
gjs: Kommando nicht gefunden.
gjs: kommandot finns inte
gjs: komut yok
gjs: nie znaleziono polecenia
gjs: níor aimsíodh an t-ordú
gjs: no se encontró la orden
gjs: no s'ha trobat l'ordre
gjs: opdracht niet gevonden
gjs: parancs nem található
gjs: perintah tidak ditemukan
gjs: príkaz nenájdený
gjs: příkaz nenalezen
gjs: команда не найдена
gjs: командата не е открита
gjs: 命令找不到
gjs: コマンドが見つかりません