Glossary

This glossary defines common terms used throughout the MicroPython Stubber documentation.

General Terms

Board : A physical microcontroller development board (e.g., ESP32, Raspberry Pi Pico, PyBoard) that runs MicroPython firmware.

CPython : The reference implementation of Python, typically running on desktop/server systems. Different from MicroPython in available modules and memory constraints.

Firmware : The MicroPython software that runs on a microcontroller board. Different firmware versions support different modules and features.

Firmware ID : A unique identifier for a specific firmware build, typically including family, version, and port (e.g., micropython-v1.22.2-esp32).

IDE : Integrated Development Environment - a software application providing comprehensive facilities for software development (e.g., VS Code, PyCharm).

IntelliSense : Microsoft’s code completion, parameter info, quick info, and member lists feature in VS Code and other editors.

MCU : Microcontroller Unit - the chip that runs MicroPython firmware as part of a product or on a development board.

Port : A version of MicroPython adapted for a specific microcontroller family or platform (e.g., esp32, rp2, stm32).

REPL : Read-Eval-Print Loop - the interactive MicroPython prompt where you can type commands and see immediate results.

Stub-Related Terms

Core Stubs : Stub files for Python standard library modules that provide compatibility between MicroPython and CPython.

Doc Stubs : Stub files generated by parsing the official MicroPython documentation (RST files). These include detailed parameter information and docstrings.

Frozen Modules : Python modules that are compiled into the MicroPython firmware at build time to save memory. These modules are stored in flash memory rather than as separate .py files.

Frozen Stubs : Stub files generated from the source code of frozen modules found in MicroPython firmware repositories.

Firmware Stubs : Stub files generated directly on a MicroPython device by introspecting available modules and their attributes (previously called MCU stubs; the mcu-stubs CLI alias remains available). These have limited parameter information due to memory constraints. The stored stub source name remains “MCU stubs” for database and manifest compatibility.

Minified Stubs : Compressed versions of stub generation scripts optimized for deployment on memory-constrained MicroPython devices.

Module Manifest : A JSON file (modules.json) that contains metadata about generated stubs, including board information, firmware version, and list of successfully stubbed modules.

Stub Files : Python files with .pyi extensions that contain type hints and interface definitions without implementation code. Used by IDEs and type checkers for code completion and error detection.

Type Hints : Annotations in Python code that specify the expected types of variables, function parameters, and return values, following PEP 484 standards.

Tools and Commands

createstubs.py : The main script that runs on MicroPython devices to generate stub files by introspecting available modules.

mpremote : A command-line tool for interacting with MicroPython devices over serial connections.

Pylance : Microsoft’s Python language server that provides IntelliSense, type checking, and other language features in VS Code.

stubgen : A tool (part of mypy) that automatically generates stub files from Python source code.

stubber : The main command-line interface for MicroPython Stubber, providing various subcommands for stub generation and management.

File Extensions and Formats

.py Files : Regular Python source code files containing implementation.

.pyi Files : Python stub files containing only type information and interface definitions, no implementation.

modules.json : A manifest file containing metadata about generated stubs and the device they were created on.

MicroPython-Specific Terms

sys.implementation : A Python module attribute that provides information about the Python implementation (name, version, etc.).

sys.uname() : A MicroPython function that returns system information including platform, architecture, and version details.

upip : MicroPython’s package installer (predecessor to mip).

mip : MicroPython’s modern package installer for installing packages from PyPI or other sources.

Flash Memory : Non-volatile storage on microcontroller boards where firmware and frozen modules are stored.

SD Card : External storage that can be used with some MicroPython boards for additional file storage.

Development Workflow Terms

Clone : To create a local copy of a Git repository, typically the MicroPython source code repositories.

Repository (Repo) : A Git repository containing source code, typically hosted on GitHub.

Switch : To change between different versions, branches, or commits in a Git repository.

Merge : To combine different types of stub files (doc, frozen, MCU) into a unified set.

Build : To create distributable packages from stub files for publication to PyPI.

Publish : To upload stub packages to PyPI or other package repositories.

Version : A specific release or commit of MicroPython firmware (e.g., v1.22.2, stable, preview).

Configuration Terms

pyproject.toml : A configuration file used by modern Python tools including Poetry for project metadata and dependencies.

Pylint : A Python static code analysis tool that looks for programming errors, helps enforce coding standards, and suggests refactoring.

Type Checking : The process of verifying that code uses types consistently and correctly, typically done by tools like mypy or Pylance.

Workspace : A VS Code concept representing a folder or set of folders that contain your project files and configuration.

Error and Debugging Terms

Memory Allocation Bug : A specific issue in MicroPython 1.13.0 that prevents stub generation from working properly.

NotImplementedError : A Python exception raised when attempting to use functionality that isn’t available or implemented.

Problematic Modules : MicroPython modules that cannot be safely introspected for stub generation due to side effects or system requirements.

Excluded Modules : Modules that are intentionally skipped during stub generation because they provide no useful type information.

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This glossary is maintained as part of the MicroPython Stubber documentation. Terms are added and updated as the project evolves.