builder: 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/builder - from package: golang-go.tools

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

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