Upsolver is described as 'In-Memory Data Preparation Platform. It removes the complexity from Big Data and Real-Time projects and shortens their implementation time from weeks/months to several hours, literally'. There are three alternatives to Upsolver, not only websites but also apps for Linux, Mac, Windows and BSD. The best alternative is Apache Spark, which is both free and Open Source. Other great sites and apps similar to Upsolver are Apache Hadoop (Free, Open Source) and Apache Flink (Free, Open Source).
Apache Spark™ is a fast and general engine for large-scale data processing. Speed Run programs up to 100x faster than Hadoop MapReduce in memory, or 10x faster on disk. Spark has an advanced DAG execution engine that supports cyclic data flow and in-memory computing.
Apache Hadoop is a open source software framework that supports data-intensive distributed applications licensed under the Apache v2 license. It enables applications to work with thousands of computational independent computers and petabytes of data.