What Is the License for Automattic Harper? Apache 2.0 Terms Explained

The Harper codebase is released under the Apache License, Version 2.0, a permissive open source license that permits commercial use, modification, and distribution provided you retain copyright notices and include a copy of the license.

The Automattic Harper repository is a grammar and spell checking engine distributed under a permissive open source license. If you are integrating Harper into your project or contributing code, understanding the Automattic Harper license terms ensures you comply with attribution requirements and leverage the patent grant protections.

Apache License 2.0: The Official Harper License

The Automattic Harper license is the Apache License, Version 2.0. You can find the complete legal text in the repository's top-level LICENSE file, which governs all source code in the project unless explicitly stated otherwise. The same Apache 2.0 license also appears in the packages/chrome-plugin/LICENSE path for the Chrome extension sub-package.

Key Terms and Conditions

The Apache 2.0 license governing Harper balances broad permissions with specific responsibilities.

Usage Permissions

You may use, reproduce, modify, distribute, and sublicense the Harper source code for any purpose, including commercial applications, without paying royalties. This includes embedding the grammar checker in proprietary software or SaaS products.

Attribution Requirements

Every redistribution must preserve the copyright notice, include a copy of the Apache 2.0 license text, and document any modifications made to the original files. Failure to retain the LICENSE file contents violates the license terms.

Patent Grant

Contributors to Automattic Harper provide a royalty-free patent license to users. This protects you from patent claims by contributors regarding their contributions to the project, a feature not present in all open source licenses.

Warranty Disclaimer

The software is provided "as is" without warranties of any kind. Contributors are not liable for damages arising from the use of Harper, even if advised of the possibility of such damages.

Applying License Headers to New Files

When contributing new files to Harper, include the standard Apache 2.0 header to clearly mark the licensing terms.

For Rust source files:

//! Copyright 2024 Elijah Potter
//! Licensed under the Apache License, Version 2.0 (the "License");
//! you may not use this file except in compliance with the License.
//! You may obtain a copy of the License at
//!     http://www.apache.org/licenses/LICENSE-2.0
//!
//! Unless required by applicable law or agreed to in writing, software
//! distributed under the License is distributed on an "AS IS" BASIS,
//! WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//! See the License for the specific language governing permissions and
//! limitations under the License.

For JavaScript modules:

/*
 * Copyright 2024 Elijah Potter
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

Summary

• The Automattic Harper license is Apache License, Version 2.0, located in the repository root LICENSE file and duplicated at packages/chrome-plugin/LICENSE.
• You may use Harper commercially, modify the code, and distribute derivatives without royalty payments.
• Redistributions must include the original copyright notice, a copy of the license, and documentation of changes.
• The license includes an express patent grant from contributors and disclaims liability warranties.

Frequently Asked Questions

Is Automattic Harper open source?

Yes. Harper is released under the Apache License 2.0, an OSI-approved open source license that provides complete source code access and permits modification and redistribution under clear terms.

Can I use Harper in commercial projects?

Yes. The Apache 2.0 license explicitly permits commercial use, including integrating the grammar engine into proprietary applications or hosted services, provided you include the required attribution and license notice.

What file contains the full license text?

The complete Apache License 2.0 text resides in the LICENSE file at the repository root. An identical copy exists at packages/chrome-plugin/LICENSE for the Chrome extension package.

Do I need to include a license header in every file I modify?

While the top-level LICENSE file governs the entire repository, adding the Apache 2.0 header to new or substantially modified files is recommended practice. This clarifies the licensing terms for individual files and ensures compliance even if they are later distributed separately from the full repository.

{
  "mcpServers": {
    "instagit": {
      "command": "npx",
      "args": ["-y", "instagit@latest"]
    }
  }
}