Clear magic is built on compile time. Therefore, the impact on loading time is very limited. Clear can be used for example into web function (lambda function, google cloud function) application without any problem.
The only overhead is the connection to the database; Clear allocate by default 5 connections to PostgreSQL. In the case of mono-fiber web-function projects, you may want to reduce the connection pool to 1 only:
Here is a simple benchmark comparing the different layers of Clear and how they impact the performance, over a 100k row very simple table:
With Model: With attributes and cursor 7.4 (135.09ms) (± 6.44%) 116409530 B/op 5.64× slower
With Model: With cursor 8.61 (116.08ms) (± 2.82%) 97209247 B/op 4.84× slower
With Model: With attributes 13.78 ( 72.59ms) (± 3.61%) 83101520 B/op 3.03× slower
With Model: Simple load 100k 16.41 ( 60.94ms) (± 3.22%) 63901872 B/op 2.54× slower
Hash from SQL only 30.21 ( 33.1ms) (± 5.18%) 22354496 B/op 1.38× slower
Using: Model::Collection#pluck 41.74 ( 23.96ms) (± 8.35%) 25337128 B/op fastest
Clear stands in the middle of the crowd, being slightly slower than some other ORM over
More noticeably, Clear performs 5 to 8x faster than Ruby's ActiveRecord !