<strong>An open source toolkit for building high-quality software with any AI coding agent — a ready-to-use spec-driven process (or bring your own), endlessly extensible, community-driven, and built for your whole organization.</strong>
Spec-Driven Development **flips the script** on traditional software development. For decades, code has been king — specifications were just scaffolding we built and discarded once the "real work" of coding began. Spec-Driven Development changes this: **specifications become executable**, directly generating working implementations rather than just guiding them.
Requires **[uv](https://docs.astral.sh/uv/)** ([install uv](./docs/install/uv.md)). Replace `vX.Y.Z` with the latest release tag from [Releases](https://github.com/github/spec-kit/releases) — keep the leading `v` (for example, `v0.12.11`, not `0.12.11`):
To check for updates or upgrade the installed CLI, use the self-management commands. See the [Upgrade Guide](./docs/upgrade.md) for detailed scenarios and customization options.
```bash
# Check whether a newer release is available (read-only — does not modify anything)
specify self check
# Preview what would run, without actually upgrading
specify self upgrade --dry-run
# Upgrade in place to the latest stable release (auto-detects uv tool vs pipx install)
specify self upgrade
# Or pin a specific release tag (replace vX.Y.Z[suffix] with your desired release tag)
specify self upgrade --tag vX.Y.Z[suffix]
```
Bare `specify self upgrade` executes immediately, matching the no-prompt behavior of commands like `pip install -U` and `npm update`. For `uv tool` installs, it runs `uv tool install specify-cli --force --from <git ref>` under the hood so pinned release tags work, including dev, alpha/beta/rc, or build metadata suffixes. `uvx` (ephemeral) runs and source checkouts are detected and produce path-specific guidance instead of running an installer. Set `SPECIFY_UPGRADE_TIMEOUT_SECS` to cap how long the installer subprocess may run (default: no timeout — interrupt with `Ctrl+C` if needed).
Launch your coding agent in the project directory. Most agents expose spec-kit as `/speckit.*` slash commands; Codex CLI in skills mode uses `$speckit-*` instead; GitHub Copilot CLI uses `/agents` to select the agent or address it directly in a prompt.
Use the **`/speckit.constitution`** command to create your project's governing principles and development guidelines that will guide all subsequent development.
/speckit.specify Build an application that can help me organize my photos in separate photo albums. Albums are grouped by date and can be re-organized by dragging and dropping on the main page. Albums are never in other nested albums. Within each album, photos are previewed in a tile-like interface.
/speckit.plan The application uses Vite with minimal number of libraries. Use vanilla HTML, CSS, and JavaScript as much as possible. Images are not uploaded anywhere and metadata is stored in a local SQLite database.
[](https://www.youtube.com/watch?v=a9eR1xsfvHg&pp=0gcJCckJAYcqIYzv)
> Community contributions are independently created and maintained by their respective authors. Review source code before installation and use at your own discretion.
Want to contribute? See the [Extension Publishing Guide](extensions/EXTENSION-PUBLISHING-GUIDE.md), the [Presets Publishing Guide](presets/PUBLISHING.md), or the [Community Bundles guide](docs/community/bundles.md).
Spec Kit works with 30+ AI coding agents — both CLI tools and IDE-based assistants. See the full list with notes and usage details in the [Supported AI Coding Agent Integrations](https://github.github.io/spec-kit/reference/integrations.html) guide.
After running `specify init`, your AI coding agent will have access to these slash commands for structured development. For integrations that support skills mode, passing `--integration <agent> --integration-options="--skills"` installs agent skills instead of slash-command prompt files.
## 🧩 Making Spec Kit Your Own: Extensions & Presets
Spec Kit can be tailored to your needs through two complementary systems — **extensions** and **presets** — plus project-local overrides for one-off adjustments:
- **Templates** are resolved at **runtime** — Spec Kit walks the stack top-down and uses the first match.
- Project-local overrides (`.specify/templates/overrides/`) let you make one-off adjustments for a single project without creating a full preset.
- **Extension/preset commands** are applied at **install time** — when you run `specify extension add` or `specify preset add`, command files are written into agent directories (e.g., `.claude/commands/`).
- If multiple presets or extensions provide the same command, the highest-priority version wins. On removal, the next-highest-priority version is restored automatically.
- If no overrides or customizations exist, Spec Kit uses its core defaults.
Use **extensions** when you need functionality that goes beyond Spec Kit's core. Extensions introduce new commands and templates — for example, adding domain-specific workflows that are not covered by the built-in SDD commands, integrating with external tools, or adding entirely new development phases. They expand *what Spec Kit can do*.
```bash
# Search available extensions
specify extension search
# Install an extension
specify extension add <extension-name>
```
For example, extensions could add Jira integration, post-implementation code review, V-Model test traceability, or project health diagnostics.
See the [Extensions reference](https://github.github.io/spec-kit/reference/extensions.html) for the full command guide. Browse the [community extensions](https://github.github.io/spec-kit/community/extensions.html) for what's available.
Use **presets** when you want to change *how* Spec Kit works without adding new capabilities. Presets override the templates and commands that ship with the core *and* with installed extensions — for example, enforcing a compliance-oriented spec format, using domain-specific terminology, or applying organizational standards to plans and tasks. They customize the artifacts and instructions that Spec Kit and its extensions produce.
```bash
# Search available presets
specify preset search
# Install a preset
specify preset add <preset-name>
```
For example, presets could restructure spec templates to require regulatory traceability, adapt the workflow to fit the methodology you use (e.g., Agile, Kanban, Waterfall, jobs-to-be-done, or domain-driven design), add mandatory security review gates to plans, enforce test-first task ordering, or localize the entire workflow to a different language. The [pirate-speak demo](https://github.com/mnriem/spec-kit-pirate-speak-preset-demo) shows just how deep the customization can go. Multiple presets can be stacked with priority ordering.
See the [Presets reference](https://github.github.io/spec-kit/reference/presets.html) for the full command guide, including resolution order and priority stacking.
For support, please open a [GitHub issue](https://github.com/github/spec-kit/issues/new). We welcome bug reports, feature requests, and questions about using Spec-Driven Development.
