Alexander S.Private profile: Upwork shows its earnings only to signed-in members, so we check it every few weeks, not daily. MRR here is a rough estimate (Upwork's six-month earnings ÷ months active). Last read Nov 5, 2026.

Programming languages: Scala, Java, Python, C/C++, Go Frameworks: Play Framework, Spring boot, Akka Streams, Cats Effect, Fs2 Databases: MySQL, Oracle, Postgres, Redis Data Engineering: Building ETL processes with the following tools: Apache Spark, Hadoop, HDFS, YARN, Hive, HBase, Oozie, Cloudera, Elastic Search, Kafka, Airflow DevOps: Docker, Kubernetes, Openshift, Jenkins Other tools and technology: Familiar with: Cassandra, MongoDB, AWS Operating systems: Linux (expert knowledge)