https://docs.confluent.io/platform/current/schema-registry/index.html
https://docs.confluent.io/platform/current/schema-registry/serdes-develop/serdes-avro.html
https://docs.confluent.io/platform/current/schema-registry/schema_registry_tutorial.html
https://docs.confluent.io/platform/current/schema-registry/installation/index.html#installing-and-configuring-sr

https://github.com/confluentinc/schema-registry

compat-level
    https://docs.confluent.io/platform/current/schema-registry/avro.html#compatibility-types
    sandbox - backward
    prod - full

optional field always has default value
    https://avro.apache.org/docs/1.11.1/specification/#schema-record

tools - schema-registry-ui
https://github.com/lensesio/schema-registry-ui
    0.9.5

2025
Otus - Kafka and Schema Registry 0:00 of 1:43:17
    https://www.youtube.com/watch?v=RjlvTYDf60E
2023
https://habr.com/ru/company/lenta_utkonos_tech/blog/715298/
2022
https://habr.com/ru/post/678144/
2021
https://habr.com/ru/company/alfastrah/blog/547092/
2020
https://habr.com/ru/post/492312/
    https://github.com/avrylkov/avro-kafka
2019
https://medium.com/swlh/exploit-apache-kafkas-message-format-to-save-storage-and-bandwidth-7e0c533edf26
2018
https://www.confluent.io/blog/decoupling-systems-with-apache-kafka-schema-registry-and-avro/
2017
https://medium.com/@stephane.maarek/introduction-to-schemas-in-apache-kafka-with-the-confluent-schema-registry-3bf55e401321