cmake: command not found on macOS

After adding this line in my Podfile:

pod 'PiwikTracker', :git => 'https://github.com/manuroe/matomo-sdk-ios.git', :branch => 'feature/CustomVariables'

The below error is occuring:

[!] /bin/bash -c set -eecho `pwd`sed -i '''s/include <\(cmark.*\)>/include "\1"/' src/cmark.hmkdir -p build; cd build && cmake -G Xcode ../Users/mac1/Library/Caches/CocoaPods/Pods/Release/cmark/0.24.1-ec027/bin/bash: line 4: cmake: command not found

Can anyone help me with this issue?