Extension marketplace

An extension marketplace is the registry of installable add-ons for an IDE — VS Code Marketplace, OpenVSX, Cursor extensions, JetBrains Plugins, Zed extensions. The size + quality of the marketplace is a major IDE differentiator in 2026.

Extension marketplaces shape developer productivity: a missing extension = a workflow gap. VS Code Marketplace is the largest (~50K extensions, MS-controlled); OpenVSX is the open alternative (used by VS Codium, Cursor, Theia); JetBrains Plugins is curated + paid-friendly; Cursor inherits VS Code's marketplace via VSIX compat; Zed maintains its own smaller marketplace; Neovim has no central marketplace (LazyVim / packer / lazy.nvim handle plugin install). For AI-tool builders: shipping to VS Code Marketplace gives biggest reach; OpenVSX gives open-source friendly distribution; JetBrains gives enterprise reach. Quality varies — popular extensions are often unmaintained, security incidents (malicious extensions) happen.

When to use extension marketplace

• Picking an IDE.
• Shipping AI tooling for IDE users.

Common mistakes

• Installing extensions without audit — supply-chain risk is real.

FAQ

Related terms

• AI IDE — An AI IDE is a code editor with AI features built into the core editing experience — inline completion, chat panel, agent mode, codebase RAG, MCP server integration. Cursor, Zed, Windsurf, JetBrains with AI Assistant, VS Code with Copilot are 2026 leaders.
• Language Server Protocol (LSP) — LSP is the open standard for editor ↔ language tooling communication — autocomplete, jump-to-definition, find references, diagnostics — used by VS Code, Zed, Neovim, JetBrains, and most modern IDEs in 2026.

Last updated: 2026-06-01. Raw markdown: https://promtable.com/glossary/extension-marketplace.md.