In order to facilitate the packaging of applications by providing successive steps to achieve, each package is assigned a quality level, from 0 to 10.
A package must meet a number of criteria to reach each level. In addition, to reach a level, the package must have previously reached the previous level.
This classification of applications by levels has 3 advantages:
- The application packaging is more fun, with clear objectives to achieve and successive steps.
- A properly packaged application is put forward more than an application that does not comply with packaging rules.
- Users can quickly see the level of an application and thus know if the package is of good quality.
## Level summary
**Level 0**
The application does not work.
**Level 1**
The application installs and uninstalls correctly in some cases.
**Level 2**
The application installs and uninstalls correctly in all common configurations.
**The application does not install or run after installation.**
This is the lowest level, a level 0 application is considered non-functional.
YEP to be respected to reach level 0:
- [YEP 1.1](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-11---nommer-son-app-et-son-d%C3%A9pot---valid%C3%A9--manuel--notworking-) Name your app and repository
- [YEP 1.2](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-12---inscrire-lapp-sur-un-r%C3%A9pertoire-connu---valid%C3%A9--manuel--notworking-) Add the app to a known app list
### Level 1
**The application can be installed and uninstalled correctly.**
But exceptions are possible, if at least one installation method is functional and its removal then the application is considered functional.
YEP to be respected to reach level 1:
- [YEP 2.2](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-22---utiliser-bash-pour-les-scripts-principaux---valid%C3%A9--auto--working-) Use bash for main scripts
- [YEP 2.7](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-27---donner-des-permissions-suffisantes-aux-instructions-bash----valid%C3%A9--auto--working-) Bash instructions: Give sufficient permissions to bash instructions
- [YEP 2.15](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-215---v%C3%A9rifier-les-param%C3%A8tres-saisies-par-lutilisateur----valid%C3%A9--manuel--official-) : Follow the application installation instructions
### Level 2
**The application can be installed and uninstalled in all common configurations.**
- Installation in subfolder.
- Installation at the root of a domain or subdomain.
- Private installation (secured by the SSO).
- Public installation.
- Multi-instance installation.
- Uninstallation under the same circumstances.
*If an application does not allow certain installation configurations, these must be clearly indicated in the README. However, level 2 cannot be reached if an installation configuration is intentionally discarded without valid reason.*
*This does not preclude the voluntary restriction of public, private or multi-instance if it is relevant for this application.*
YEP to be respected to reach level 2:
- [YEP 1.5](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-15---mettre-%C3%A0-jour-r%C3%A9guli%C3%A8rement-le-statut-de-lapp---brouillon--manuel--working-) : Update app status regularly
- *[YEP 2.18.2](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-2182---supporter-linstallation-sur-un-domaine----valid%C3%A9--auto--working-) : Support installation on a domain*
- *[YEP 2.18.3](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-2183---supporter-linstallation-sur-un-sous-domaine----valid%C3%A9--auto--working-) : Support installation on a subdomain*
- *[YEP 2.18.4](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-2184---supporter-linstallation-sur-un-sous-dossier----valid%C3%A9--auto--official-) : Support installation on a subfolder*
**The application supports upgrade from an older version of the package.**
The application must be able to be updated from a previous version of the package without causing an error.
YEP to be respected to reach level 3:
- [YEP 2.3](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-23---sauvegarder-les-r%C3%A9ponses-lors-de-linstallation---valid%C3%A9--manuel--working-) Save answers during installation
- *[YEP 4.3](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-43---fournir-un-script-de-sauvegarde-yunohost-fonctionnel----valid%C3%A9--auto--official-) : Provide a functional YunoHost backup script*
- *[YEP 4.4](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-44---fournir-un-script-de-restauration-yunohost-fonctionnel----valid%C3%A9--auto--official-) : Provide a functional YunoHost restore script*
**The application has no errors in [Package linter](https://github.com/YunoHost/package_linter).**
*There may be false positives in Package linter. These situations will be handled on a case-by-case basis.*
YEP to be respected to reach level 5:
- *[YEP 1.3](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-13---indiquer-la-licence-associ%C3%A9e-au-paquet---valid%C3%A9--auto--working-) : Specify the license associated with the package*
- [YEP 2.12](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-212---utiliser-les-commandes-pratiques-helpers---valid%C3%A9--auto--official-) : Use practical commands (helpers)
- [YEP 2.18.1](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-2181---lancer-le-script-dinstallation-dune-webapp-correctement----valid%C3%A9--manuel--working-) : Run the webapp installation script correctly
### Level 6
**The application can be backed up and restored without error on the same machine or another.**
YEP to be respected to reach level 6:
- [YEP 1.4](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-14---informer-sur-lintention-de-maintenir-un-paquet----brouillon--manuel--working-) : Inform about the intention to maintain a package
- [YEP 1.6](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-16---se-tenir-inform%C3%A9-sur-l%C3%A9volution-du-packaging-dapps---valid%C3%A9--manuel--official-) : As a maintainer, keep checking and being aware of the evolution of apps packaging
- *[YEP 1.7](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-17---ajouter-lapp-%C3%A0-lorganisation-yunohost-apps---valid%C3%A9--manuel--official-) : Add app to the [YunoHost-Apps organization](https://github.com/YunoHost-Apps)*
- [YEP 1.10](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-110---garder-un-historique-de-version-propre----brouillon--manuel--official-) : Keep a clean version history
- [YEP 2.9](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-29---enlever-toutes-traces-de-lapp-lors-de-la-suppression----brouillon--manuel--working-) : Remove all traces of the app during deletion
- [YEP 3.3](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-33---faciliter-le-contr%C3%B4le-de-lint%C3%A9grit%C3%A9-des-sources----brouillon--manuel--official-) : Facilitating source integrity control
- [YEP 3.5](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-35---suivre-les-recommendations-de-la-documentation-de-lapp----valid%C3%A9--manuel--official-) : Follow the recommendations of the app documentation
- [YEP 2.8](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-28---modifier-correctement-une-configuration-syst%C3%A8me----brouillon--manuel--working-) : Change a system configuration correctly
- [YEP 2.11](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-211---utiliser-une-variable-plut%C3%B4t-que-lapp-id-directement---valid%C3%A9--manuel--official-) : Use a variable rather than the app id directly
- [YEP 2.13](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-213---traduire-le-package-en-anglais----brouillon--manuel--official-) : Translate the package into English
- [YEP 3.2](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-32---ouvrir-un-port-correctement----brouillon--manuel--working-) : Open port: Open port correctly
- *[YEP 2.16](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-216---v%C3%A9rifier-la-disponibilit%C3%A9-des-d%C3%A9pendances-sur-arm-x86-et-x64----valid%C3%A9--manuel--official-) : Check dependency availability on ARM, x86 and x64*
- [YEP 2.18.5](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-2185---ajouter-la-tuile-yunohost-pour-naviguer-facilement-entre-les-applications----valid%C3%A9--manuel--official-) : Add the YunoHost tile to easily navigate between applications
- [YEP 4.1](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-41---lier-au-ldap----valid%C3%A9--manuel--official-) : Link to ldap
- [YEP 4.2](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-42---lier-lauthentification-au-sso----valid%C3%A9--manuel--official-) : Bind authentication to sso
- [YEP 4.5](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-45---utiliser-les-hooks----valid%C3%A9--manuel--optional-) : Use hooks
If an application is not available on an architecture, and it is impossible to circumvent this limitation reasonably, this limitation must be indicated in the REDME and taken into account in the installation script. The installation of the application on an unsupported architecture must be stopped before modifying the filesystem.
### Level 9
**The application complies with all optional YEPs.**
YEP to be respected to reach level 9:
- [YEP 2.14](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-214---remplir-correctement-un-fichier-de-conf----brouillon--manuel--official-) : Fill a conf file correctly
- [YEP 2.17](https://github.com/YunoHost/doc/blob/master/packaging_apps_guidelines_fr.md#yep-217---prendre-en-compte-la-version-dorigine-lors-des-mises-%C3%A0-jour----valid%C3%A9--manuel--official-) : Take into account the original version during updates