Mastering Python Development in VS Code: March 2026 Features Guide

Overview

Welcome to the March 2026 release of the Python extension for Visual Studio Code! This update brings two powerful enhancements that will supercharge your coding workflow: searching Python symbols inside installed packages and an experimental Rust-based parallel indexer. Whether you're navigating a familiar codebase or exploring a new library, these features help you find definitions faster and keep IntelliSense responsive—even on large projects.

Mastering Python Development in VS Code: March 2026 Features Guide — Source: devblogs.microsoft.com

This guide will walk you through everything you need to know to set up and use these features effectively. By the end, you'll be able to:

Locate functions, classes, and variables from third-party packages directly in your workspace symbol search.
Enable a blazing-fast indexing engine that drastically reduces startup delays and improves autocompletions.

Prerequisites

Before diving in, ensure your environment is ready:

Visual Studio Code (latest stable version) installed.
The Python extension (ms-python.python) and Pylance (ms-python.vscode-pylance) are both updated to the March 2026 release or later.
A Python project that uses a virtual environment (e.g., .venv or venv) containing installed packages.
Familiarity with VS Code's Settings UI and settings.json file.

Step-by-Step Instructions

1. Enabling Symbol Search in Installed Packages

One of the most common frustrations when working with unfamiliar libraries is finding where a symbol is actually defined. Now Pylance can include symbols from packages installed in your active virtual environment in the Workspace Symbol search (Cmd/Ctrl+T).

What does this do?

When you press Cmd/Ctrl+T and start typing, results now include symbols from site-packages in your active virtual environment.
You can navigate directly into third-party library code without leaving VS Code or searching documentation.
For libraries without py.typed, only symbols exported via __init__.py or __all__ are shown, keeping the list focused and relevant.

How to enable it:

Open VS Code's settings: Cmd/Ctrl+,.
Search for Include Venv In Workspace Symbols.
Check the box under Python › Analysis (the setting name is python.analysis.includeVenvInWorkspaceSymbols).

Alternatively, add this line to your settings.json:

"python.analysis.includeVenvInWorkspaceSymbols": true

Fine-tuning with Package Index Depths

Because indexing installed packages can impact performance, you can control how deeply Pylance searches into sub-modules for each package. This setting is found at:

Python › Analysis: Package Index Depths (python.analysis.packageIndexDepths)

It expects an array of objects specifying package name and depth (e.g., [{"name": "numpy", "depth": 1}]). This allows you to limit deep indexing only to packages you frequently use, while leaving others at a shallow level.

Pro tip: This feature is opt-in by design—your default experience remains unchanged. Enable it only when you need rich cross-package navigation.

2. Activating the Experimental Rust-Based Parallel Indexer

The engine behind completions, auto-imports, and workspace symbol search—Pylance’s indexer—has been rewritten in Rust and runs out-of-process. In internal tests, this new indexer is on average 10× faster on large Python projects. The result: snappier IntelliSense after opening your workspace and a more responsive editor overall.

Important: This is an experimental feature. We want to validate its performance and reliability across different project setups before it becomes the default.

How to enable:

Open Settings (Cmd/Ctrl+,).
Search for Parallel Indexing.
Check Enable Parallel Indexing (Experimental) under Python › Analysis (python.analysis.enableParallelIndexing).

Or directly add to settings.json:

"python.analysis.enableParallelIndexing": true

Important step after enabling: Reload VS Code to ensure the new indexer starts cleanly. Use Cmd/Ctrl+Shift+P, type Reload Window, and press Enter. Without this, the change may not take effect.

This setting has the most impact on larger projects (e.g., with hundreds of files or many installed packages). Small projects may see little difference, but won’t be harmed.

We want your feedback! If you try this and notice faster completions, slower behavior, or any issues, please let us know via the VS Code Python extension GitHub repository.

Common Mistakes to Avoid

Forgetting to reload VS Code after enabling parallel indexing. The new indexer only starts on a fresh window. Without reloading, you'll still be using the old indexer.
Assuming symbol search automatically indexes all packages. The inclusion of virtual environment symbols is opt-in. If you haven’t enabled python.analysis.includeVenvInWorkspaceSymbols, you won’t see third-party symbols.
Not having an active virtual environment. Both features rely on knowing which environment is active. If no environment is selected, the settings won’t have the intended effect.
Expecting dramatic improvements on tiny projects. The parallel indexer shines when there’s a lot to index. On a single-file script, you might not notice any speedup.
Misunderstanding the "package index depths" setting. It expects an array of objects, not a number. Using an invalid format will be silently ignored or cause an error.
Conflicting settings from older versions. If you previously modified python.analysis.indexing or other obsolete settings, they may interfere. Stick to the new setting names.

Summary

The March 2026 Python extension release offers two game-changing features: the ability to search symbols in installed packages (opt-in via python.analysis.includeVenvInWorkspaceSymbols) and an experimental Rust-based parallel indexer (enabled with python.analysis.enableParallelIndexing). Together, they make exploring new libraries faster and keep IntelliSense snappy even on large codebases. Try them today, and don’t forget to reload VS Code after enabling the parallel indexer. Your feedback helps shape the future of Python development in VS Code!