# \[Discussion\] Why not PSR-15?

**URL:** <https://discourse.cakephp.org/t/discussion-why-not-psr-15/4857>\
**Category:** Uncategorized\
**Created:** [September 4, 2018, 10:00am UTC](https://discourse.cakephp.org/t/discussion-why-not-psr-15/4857 "2018-09-04T10:00:37Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![filkaris](https://yyz1.discourse-cdn.com/flex029/user_avatar/discourse.cakephp.org/filkaris/32/1078_2.png) [@filkaris](https://discourse.cakephp.org/u/filkaris)\
**Post date:** [September 4, 2018, 10:00am UTC](https://discourse.cakephp.org/t/discussion-why-not-psr-15/4857/1 "2018-09-04T10:00:37Z")

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I just started learning about middleware and noticed that cakePHP does not follow the PSR-15, although it does follow PSR-7.

Is there a strategic reason for this? Since middleware was introduced recently in 3.5.0 I wouldn’t think there are backwards compatibility issues.

I’m not criticizing or anything, more of a newbie question to understand the logic behind this. Maybe PSR-15 support is planned for the future?

Thanks 🙂

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**Author:** ![markstory](https://yyz1.discourse-cdn.com/flex029/user_avatar/discourse.cakephp.org/markstory/32/182_2.png) [@markstory](https://discourse.cakephp.org/u/markstory)\
**Post date:** [September 4, 2018, 1:53pm UTC](https://discourse.cakephp.org/t/discussion-why-not-psr-15/4857/2 "2018-09-04T13:53:00Z")

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There isn’t a strategic reason. The PSR15 spec was finalized _well_ after we had adopted PSR7 and the ‘two-pass’ middleware approach used by other frameworks using PSR7.

Supporting PSR15 is something I would like to do in the future. Right now PSR15 in isolation makes creating responses challenging as doing so requires coupling to a concrete response class. However, [PSR17 can solve this](https://www.php-fig.org/psr/psr-17/).

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**Author:** ![filkaris](https://yyz1.discourse-cdn.com/flex029/user_avatar/discourse.cakephp.org/filkaris/32/1078_2.png) [@filkaris](https://discourse.cakephp.org/u/filkaris)\
**Post date:** [September 4, 2018, 7:18pm UTC](https://discourse.cakephp.org/t/discussion-why-not-psr-15/4857/3 "2018-09-04T19:18:04Z")

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I see! Thanks for the clarification 🙂