git clone ''

(ql:quickload :protobuf)

Protobuf is a Common Lisp implementation of Google's protocol buffers.

The protobuf repository contains a compiler from .proto files to Lisp and the run time support needed by the generated Lisp code. Not all protocol buffer features are implemented, but the code works well enough that serialization tests pass.

The protobuf code has been tested with ABCL, CCL, CLISP, Lispworks, and SBCL. In the past it has also worked with Allegro Common Lisp, but I have not tested it recently.


  1. The Common Lisp protocol buffer compiler is implemented as a plugin to Google's protocol buffer compiler, so you must first build and install Google's compiler, which is called protoc. The required code and documentation are available here:

The steps should be something like:

cd /tmp
git clone google-protobuf
cd google-protobuf
./configure --prefix=/local/software/package/protobuf
make check
make install
  1. Clone the Lisp protobuf git repository to get a local copy and compile protoc-gen-lisp, the Common Lisp protocol buffer plugin. The steps required for Linux are:

    cd /tmp git clone git://

    cd protobuf/protoc/lisp

    Copy the config.h file created when Google's protocol buffer compiler was


    cp /tmp/google-protobuf/config.h .

    Change INSTALL_ROOT and PROTOC_ROOT in Makefile. INSTALL_ROOT indicates

    where protoc-gen-lisp should be installed. PROTOC_ROOT indicates where

    you installed Google's protobuf compiler when you compiled it in step 1.

    make install

  2. Download and install the Common Lisp packages that protobuf depends on. First, you'll need ASDF, but it comes pre-installed in most Common Lisp distributions. You'll also need, which is available via Quicklisp. To run all the tests, you'll need the Stefil testing package and its dependencies: hu.dwim.stefil, hu.dwim.asdf, alexandria. All of these can easily be downloaded using Quicklisp.

If you're not using Allegro, CLisp, or SBCL, you may need trivial-utf8, again available via Quicklisp.

  1. Make protobuf and its dependencies available to ASDF. There are several ways to do this and you should consult the ASDF documentation to determine what will work best for you. If you've downloaded dependencies using Quicklisp, then ASDF will automatically know about them.

ASDF and its manual are available here:

On my system, I tell ASDF where to find the protobuf system files by creating a file called source-registry.conf in directory /home/brown/.config/common-lisp/ with the following contents:

(:source-registry (:tree “/home/brown/src/protobuf/”) :inherit-configuration)

  1. Make sure ASDF can execute Google's protocol buffer compiler and the Common Lisp plugin. Both protoc and protoc-gen-lisp must be installed in directories that appear in your shell's PATH environment variable.

  2. Compile and load all the protobuf code:

    (asdf:load-system 'protobuf)

  3. Optionally, load and run all the tests:

    (asdf:test-system 'varint) (asdf:test-system 'protobuf)

  4. Compile and run the example code, which shows how to incorporate protocol buffer definition files into your own projects:

    (asdf:load-system 'protobuf-example)

    (in-package address-book) (add-person :id 100 :name “Robert Brown” :email-address “” :phone-numbers '((home . “718-555-1212”) (work . “212-589-1212”) (mobile . “917-555-1212”))) (list-people)


Please report bugs and send suggestions on GitHub or contact me directly. My email is robert.brown at the mail hosting site