Python 3.14 Fundamentals

Learn Python the way it is actually written in 2026. Python 3.14 Fundamentals teaches the language from first principles and pairs it with the modern toolchain professional teams use, so you finish with idiomatic, type-checked, tested code instead of outdated tutorial habits.

This book is built for engineers. If you already ship in another language and need a working command of modern Python, or you learned Python years ago and want to catch up to the current toolchain and the new 3.14 features, you start at the foundation and build up one chapter at a time. Across twelve chapters you grow a single real project, a Personal Knowledge Tracker command-line app, from an empty folder to a packaged, tested, lint-clean tool.

What you build and learn:
- A uv-managed project on Python 3.14 with a clean src layout, a pinned interpreter, and a reproducible lockfile
- Values, expressions, control flow, functions, and scope, with type hints on every signature
- Collections, comprehensions, generators, and the iterator protocol
- Files, paths, and I/O with pathlib, JSON, CSV, and Zstandard compression from the standard library
- Modules, packages, and project structure, plus adding dependencies the modern way with uv
- Classes, dataclasses, and Protocols for structural typing
- Error handling with custom exceptions, ExceptionGroup, and logging
- Async and concurrency: asyncio, TaskGroup, threads, multiprocessing, and the new free-threaded build
- Testing with pytest, type checking with mypy, and linting and formatting with ruff
- A capstone that ties the whole toolchain together into one shippable project

What is new in Python 3.14, woven in where it fits:
- Template strings (t-strings) for safe, structured text
- Deferred annotation evaluation and the annotationlib module
- Free-threaded Python for true multi-core parallelism
- Subinterpreters for isolated in-process execution
- Bracketless except and the compression.zstd module

Built to learn from, not just read: every chapter ends with a mini quiz to check your understanding, a hands-on activity, and a runnable project step. All code is type-hinted, pytest-tested, and ruff-clean, so you practice the habits that make Python projects ship.

Prerequisites: general programming experience in any language. No prior Python required. You install Python 3.14 and the modern toolchain in the first chapter.

Modern Python, from the ground up. Twelve chapters. One real project. Build it for keeps.