yesod-ghc-wrapper: 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/yesod-ghc-wrapper - from package: yesod

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

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