Courses
Hands-on courses with real sandboxes. Or follow a structured path
179 courses
advancedcobolFree
COBOL Advanced
Beyond COBOL Intermediate. File handling (sequential and indexed), SORT, REDEFINES for memory layout, calling subprograms, copybooks. The features banking and insurance systems use every day.
7 lessonsLanguages
advancedlispFree
Common Lisp Advanced
Beyond Common Lisp Intermediate. Macros in depth, special variables, closures, format directives, packages. The features behind Maxima, ACL2, and the Lisp ecosystem's reputation for power.
7 lessonsLanguages
advancedpascalFree
Pascal Advanced
Beyond Pascal Intermediate. Object Pascal classes, generics, exception handling, units (modules), file I/O. The features behind Lazarus IDE and serious Pascal applications.
7 lessonsLanguages
intermediatecppFree
C++ Intermediate
Level up from C++ Fundamentals. Pointers in depth, dynamic memory, smart pointers, RAII, the Rule of Five, move semantics, templates, and exception safety. The features that turn working code into idiomatic modern C++.
7 lessonsLanguages
advancedsqlFree
SQL Advanced
Beyond SQL Intermediate. Indexes, query optimization mental model, complex joins, JSON, advanced window functions, recursive CTEs. The features behind serious analytics and reporting.
7 lessonsLanguages
advancederlangFree
Erlang Advanced
Beyond Erlang Intermediate. gen_server behaviour, supervision trees, ETS tables, distributed Erlang concepts. The OTP toolkit that powers WhatsApp and CouchDB.
7 lessonsLanguages
advancedocamlFree
OCaml Advanced
Beyond OCaml Intermediate. Functors, GADTs, polymorphic variants, lazy evaluation, the Pervasives module. The features behind Jane Street's libraries and the Coq proof assistant.
7 lessonsLanguages
advancedperlFree
Perl Advanced
Beyond Perl Intermediate. Closures, complex data structures, Moose-style OOP, packages and exporting, special variables. The features behind serious Perl tooling and CPAN packages.
7 lessonsLanguages
advancedrFree
R Advanced
Beyond R Intermediate. Environments, lexical scoping, S4 classes, vectorization tricks, NSE basics, profvis. The features behind tidyverse and serious R packages.
7 lessonsLanguages
advancedluaFree
Lua Advanced
Beyond Lua Intermediate. Closures and upvalues deep, weak tables, sandboxing, FFI patterns, the C API mental model. The features behind embedding Lua into Redis, Roblox, Neovim.
7 lessonsLanguages
advancedelixirFree
Elixir Advanced
Beyond Elixir Intermediate. GenServer, supervision trees, OTP behaviours, Tasks and Agents, ETS basics, macros. The OTP toolkit behind WhatsApp's reliability.
7 lessonsLanguages
advancedhaskellFree
Haskell Advanced
Beyond Haskell Intermediate. Applicatives, State and Reader monads, GADTs intro, lenses basics, type families. The features you actually use in production Haskell.
7 lessonsLanguages