Cisco Developer master page: https://developer.cisco.com/
IOS XR blog page, along with resources, videos and howtos: https://xrdocs.io/
Cisco IOS-XE 16.12 programmability guide (Guest Shell, VMs, Python, NETCONF, RESTConf, ZTP): https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/prog/configuration/1612/b_1612_programmability_cg.html
Cisco NX-OS 9.3(x) programmability guide (Guest Shell, Ansible, NX-SDK, NX-API, NETCONF, RESTConf): https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/93x/progammability/guide/b-cisco-nexus-9000-series-nx-os-programmability-guide-93x.html
Cisco Ansible modules: https://www.ansible.com/integrations/networks/cisco
Ansible collection for DNA Center: https://github.com/CiscoDevNet/ansible-dnac
Ansible collection for Firepower: https://github.com/CiscoDevNet/FTDAnsible
Ansible collection for Tetration: https://github.com/CiscoDevNet/tetration-ansible-playbooks
Cisco DevNet NSO site & sandbox access: https://developer.cisco.com/site/nso/
Cisco official NSO master repository at github: https://github.com/NSO-developer
Cisco NSO 5 day training: https://github.com/NSO-developer/nso-5-day-training
Cisco NSO as Docker: https://github.com/NSO-developer/nso-docker