# Deno Land Celld License: Apache 2.0 Explained (File Locations & Compliance Guide)

> Understand the Apache 2.0 license for denoland celld. Explore file locations and compliance requirements for this permissive open-source license, allowing broad use and modification.

- Repository: [Deno/celld](https://github.com/denoland/celld)
- Tags: getting-started
- Published: 2026-09-05

---

**The denoland/celld project is released under the Apache License, Version 2.0, a permissive open-source license that allows commercial and non-commercial use, modification, and distribution.**

The **denoland/celld** repository is a Rust-based project maintained by the Deno organization, and its **licensing of denoland/celld** follows the Apache 2.0 standard common across Deno ecosystem projects. This license choice ensures broad compatibility with both open-source initiatives and proprietary software development.

## Where to Find the License Files

### Repository Root License

The definitive source for the **denoland/celld license** is the `LICENSE` file at the repository root. This file contains the complete, unmodified Apache License 2.0 text that governs all code in the project.

```

https://github.com/denoland/celld/blob/main/LICENSE

```

### Per-Crate Cargo.toml Declarations

Each Rust crate within the workspace reinforces this licensing through its [`Cargo.toml`](https://github.com/denoland/celld/blob/main/Cargo.toml) manifest. The `license = "Apache-2.0"` field appears consistently across all sub-crates.

In [`crates/celld/Cargo.toml`](https://github.com/denoland/celld/blob/main/crates/celld/Cargo.toml), the core crate declares:

```toml
[package]
name = "celld"
version = "0.1.0"
authors = ["the Deno authors"]
edition = "2021"
license = "Apache-2.0"

```

Similarly, [`crates/logic/Cargo.toml`](https://github.com/denoland/celld/blob/main/crates/logic/Cargo.toml) and [`crates/ltx/Cargo.toml`](https://github.com/denoland/celld/blob/main/crates/ltx/Cargo.toml) both repeat this identical license declaration, ensuring uniform **licensing of denoland/celld** across the entire workspace.

## What Apache 2.0 Permits

The Apache License 2.0 grants you these key rights:

- **Use** — Deploy celld in personal, academic, or commercial environments without royalty payments
- **Modify** — Create derivative works, improvements, or forks with no restriction on license changes for your own additions
- **Distribute** — Share original or modified versions in source or binary form
- **Patent protection** — Explicit patent grant from contributors to all users

### Conditions You Must Follow

Apache 2.0 requires three specific compliance actions:

1. **Retain copyright notices** — Preserve all existing copyright headers in source files
2. **Include license text** — Distribute `LICENSE` file alongside any redistributed code or binaries
3. **Document changes** — If you modify source files, add a notice describing your changes

## Compliance Checklist for Binary Redistribution

When shipping a binary built from celld source code:

```text
1. Include a copy of the LICENSE file alongside your distribution.
2. Preserve the copyright notice in the binary's about/help output.
3. If you modify source files, add a notice stating the changes you made.

```

## Workspace License Structure

| File Path | Purpose |
|-----------|---------|
| `LICENSE` | Full Apache 2.0 license text governing entire repository |
| [`Cargo.toml`](https://github.com/denoland/celld/blob/main/Cargo.toml) (root) | Workspace manifest aggregating all crates |
| [`crates/celld/Cargo.toml`](https://github.com/denoland/celld/blob/main/crates/celld/Cargo.toml) | Core crate manifest with `license = "Apache-2.0"` |
| [`crates/logic/Cargo.toml`](https://github.com/denoland/celld/blob/main/crates/logic/Cargo.toml) | Logic crate license declaration |
| [`crates/ltx/Cargo.toml`](https://github.com/denoland/celld/blob/main/crates/ltx/Cargo.toml) | LTX crate license declaration |

This multi-file approach creates redundant documentation of the **licensing of denoland/celld**, making it easy for automated tools and legal review to verify compliance status.

## Relationship to Deno Ecosystem

As implemented in `denoland/celld`, the Apache 2.0 license aligns with Deno's broader open-source strategy. The Deno runtime, standard library, and most official tools share this same licensing model, simplifying license compatibility when combining celld with other Deno projects.

## Summary

- The **denoland/celld license** is **Apache License, Version 2.0**
- Primary license file: `LICENSE` at repository root
- Each crate in `crates/*/Cargo.toml` declares `license = "Apache-2.0"`
- Permits commercial use, modification, and distribution with minimal conditions
- Requires preservation of copyright notices and inclusion of license text

## Frequently Asked Questions

### Can I use denoland/celld in a closed-source commercial product?

Yes. The Apache 2.0 license explicitly permits commercial use without requiring you to open-source your own code. You must include the `LICENSE` file and preserve copyright notices, but your proprietary additions can remain under different terms.

### Do I need to share my modifications if I fork celld?

No. Unlike GPL-style licenses, Apache 2.0 does not impose copyleft requirements. You may keep modifications private or release them under any license you choose. You only need to note that changes were made if you distribute the modified source.

### How can I programmatically verify the celld license?

Check the `license` field in any [`Cargo.toml`](https://github.com/denoland/celld/blob/main/Cargo.toml) file within the repository. For example, running `cat crates/celld/Cargo.toml | grep license` returns `Apache-2.0`. The root `LICENSE` file also contains the full license text for legal review.