Hexlet is an open platform for teaching programming which offers short two hour lessons for all developers, from beginners to the highly skilled. All lessons are comprised of two parts: theory and practical assignments.
In the Hexlet platform assignments are done in an actual real programming environment built to match those programmers use for work. This means that a lesson can include interaction with databases, complex frameworks and applications, multiple servers and other sophisticated tools. Despite this no downloads or installations are needed, as the Hexlet platform is cloud-based and runs through a web browser.
'Wikipedia' for programming skills uses Finland as a gateway to Europe - Helsinki Business Hub
February 22, 2015