Here are some articles and videos about hexagonal architecture / ports and adapters architecture to help you:

1. The original article by Alistair Cockburn:
   https://alistair.cockburn.us/hexagonal-architecture/

2. The new article "Component + Strategy generalizes Ports & Adapters":
   https://alistaircockburn.com/Articles/Component-Strategy-generalizes-Ports-Adapters#wbb1

3. The expanded explanation website by Juan Manuel Garrido de Paz:
   https://jmgarridopaz.github.io/

4. El articulo original de Alistair Cockburn en español (traducción de Juan Manuel Garrido de Paz):
   https://jmgarridopaz.github.io/content/arquitecturahexagonal.html

5. Slides from a 2009 talk by Alistair Cockburn, with explanation and several code samples:
   https://web.archive.org/web/20140329202802/http://alistair.cockburn.us/Hexagonal+Architecture+Keynote+at+Utah+Code+Camp+September+2009.pps

6. Alistair interviewed by Rodrigo Branas, talking about it:|
   https://www.youtube.com/watch?v=AOIWUPjal60
    

7. 1st video explanation by Alistair Cockburn: "Alistair in the Hexagone":
   https://www.youtube.com/watch?v=th4AgBcrEHA

8. 2nd video explanation by Alistair Cockburn, with programming by Andrés Robalino:
   https://www.youtube.com/watch?v=Sc_B6dQ6di0

9. Short videos just with drawings, by Juan Manuel Garrido de Paz:
   https://jmgarridopaz.github.io/content/hapills.html
    

10. Video programming example by Thomas Pierrain:
    https://www.youtube.com/watch?v=iALcE8BPs94 and
    https://www.youtube.com/watch?v=DAe0Bmcyt-4

11. Sample code on GitHub by Alistair Cockburn:
    https://github.com/totheralistair/SmallerWebHexagon

12. Sample code on GitHub by Juan Manuel Garrido de Paz:
    https://github.com/jmgarridopaz/bluezone
     

13. Case study, article from Netflix: “Ready for changes with Hexagonal Architecture”, March 10, 2020:
    https://netflixtechblog.com/ready-for-changes-with-hexagonal-architecture-b315ec967749
     

14. More resources:
    https://jmgarridopaz.github.io/content/resources.html

also see (randomly collected bunch of links:

• http://tpierrain.blogspot.fr/2013/08/a-zoom-on-hexagonalcleanonion.html
• Thomas Pierrain and friends dig into understanding Ports & Adapters in a 2014 discussion:
  https://github.com/Lunch-box/SimpleOrderRouting/wiki/Logbook-4#day-14-october-21th-2014.

• The slide show for the talk on this I gave at from Utah Code is https://web.archive.org/web/20140329202802/http://alistair.cockburn.us/Hexagonal+Architecture+Keynote+at+Utah+Code+Camp+September+2009.pps

• also nice elaboration with notes for himself by Duncan Nisbet at http://www.duncannisbet.co.uk/hexagonal-architecture-for-testers-part-1

• Video of Alistairs hexagonal architecture CQRS lightning talk Mountain West Ruby Conference 2010: https://www.youtube.com/watch?v=9kQ2veoeWZM.

• https://twitter.com/search?q=%22hexagonal%20architecture%22

• http://twitter.com/andrzejkrzywda/status/267420878487310336.

• (user-port only) a tiny CMS https://github.com/totheralistair/SmallWebHexagon.
• Pat Maddox starts with a Hexagonal Architecture and morphs it into Event Based and then CQRS. https://github.com/patmaddox/hexarch2.
• Lovely long detailed discussion about hexagonal architecture and Rails with BadrinathJanakiraman and Martin Fowler: http://thoughtworks.wistia.com/medias/uxjb0lwrcz.
• detailed evolution at https://github.com/Lunch-box/SimpleOrderRouting/wiki/Logbook-4#day-15-october-27th-2014.
• http://silkandspinach.net/2005/11/28/gravity-and-software-adaptability
  http://wordpress.com/tag/hexagonalarchitecture
  http://silkandspinach.net/2005/05/23/databases-as-life-support-for-domain-objects
  http://silkandspinach.net/2004/07/16/hexagonal-soup
  (ahhhhhh, seems silkandspinach might not exist any more... check web.archive.org!)
• The original presentation was on Ward Cunningham's wiki (sadly, no dates are visible): http://c2.com/cgi/wiki?HexagonalArchitecture

Comments and suggestions?