Iron Ledger

Hammerhall's developer library: texts on Java 25, from the first stream to a service on Spring Boot 4, and stories of the words programmers speak. Every text starts with a task, not a tool.

The English edition grows one cycle at a time; what isn't translated yet is in Russian. Ledger is a book of records: it records how the code is built and why.

• Articles 0–18

  From textbook Java to a service on Spring Boot 4: records and Maven, the Spring container, configuration, a database, the web, and tests at every step.

  Published 7 of 21 · next — 6 · read in order, from zero

• Tests 1–7

  The "From Red to Green" series: why tests, your first test, a red build, which cases to test, stubs, and a real database.

  Published 7 of 7 · read in order

• Streams

  The Java Stream API step by step: the pipeline, filter and map, sorting, flatMap, grouping, and collectors, with tasks in the forge.

  In the works

• Algorithms

  Sets, all-pairs comparisons, an inverted index, Jaccard, and vectors, and what each solution costs. For those who finished "Streams".

  In the works

• Word stories

  Where the words you hear on a project every day come from: cookie, bug, pull request, Docker, backlog.

  In the works