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Currently, no binaries are available for use and jsgrep must be built from source.

Building from source


  • CMake (2.8+)
  • V8 source
  • Node.js (v7+)
  • xxd

Building V8

Refer to

Run gn args and paste the following config:

is_debug = false
enable_nacl = false
enable_nacl_nonsfi = false
exclude_unwind_tables = true
icu_use_data_file = false
is_component_build = false
is_official_build = true
msan_track_origins = 0
symbol_level = 0
use_udev = false
v8_enable_i18n_support = false
v8_use_external_startup_data = false
v8_static_library = true

To see the list of available options, run:

gn args --list

To compile, run ninja:

ninja -C v8

Building jsgrep-ql

The JavaScript runtime package is needed by the jsgrep binary (the C++ part) in order to evaluate queries. The following snippet will pre-compile the JavaScript into a single .js file which is then converted to a binary object and will be embedded into the jsgrep binary by CMake.

(cd packages/jsgrep-ql; npm install && npm run build)

Building jsgrep

The environment variable V8_DIR must be set to the source directory of V8 which you built.

You'll need to run cmake to generate the makefile then run make.

mkdir build
(cd build; cmake .. && make -j5)

If you want to customize the build parameters, run ccmake .. instead of cmake...


jsgrep C++ tests

jsgrep tests can be run with the binary found at build/jsgrep-tests. You must turn on JSGREP_BUILD_TESTS in cmake in order to generate the target.

jsgrep-ql JavaScript tests

jsgrep-ql tests can be run with npm:

(cd packages/jsgrep-ql && npm test)

During development, you can run the tests interactively in watch mode by supplying -w and it's likely you'll want to use the dot reporter:

(cd packages/jsgrep-ql && npm test -- -w --reporter dot)


You'll need a bunch of terminal sessions for this:

  1. jsgrep-ql grammar build watcher:

The following will watch any changes you make to jsgrep-ql/grammar/jsgrep- and run nearleyc to generate the compiled grammar.

(cd packages/jsgrep-ql && npm run build-grammar:watch)

The output will be found at jsgrep-ql/src/grammar.js and it is required in order to build the JS bundle.

  1. jsgrep-ql bundle build watcher:

The following command will watch any changes to the evaluation source files jsgrep-ql/src/**/*.js and re-compile the bundle that will be used by the C++ backend.

(cd packages/jsgrep-ql && npm run build-bundle:watch)

The output will be found under jsgrep-ql/dist/jsgrep-ql.js.

  1. jsgrep build:

Now that you have the JS bundle ready (grammar embedded), you can compile the C++ backend:

(cd build && cmake .. && make -j10)

The output will be found at build/jsgrep.

  1. [OPTIONAL] jsgrep tests

If you want to run the C++ tests too, tell cmake to generate that target:

(cd build && cmake -DJSGREP_BUILD_TESTS=true .. && make -j10)

The binary will be found at build/jsgrep-tests.

  1. [OPTIONAL] jsgrep-ql tests:

If you want to run the JavaScript engine tests, the following snippet will re- run the tests anytime the source files change:

(cd packages/jsgrep-ql; npm run test:watch)


The MIT license. Copyright 2017 Ahmad Amireh See COPYING.

Libraries linked to by jsgrep and their respective licenses:


Syntactic grep for JavaScript.







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