V8 JavaScript Engine

project to learn and develop with V8

Root V8 source directory is @ ~/dev/v8 on local machine

Build Source and Sample(s)

  1. Follow steps at https://github.com/v8/v8/wiki/Building-from-Source up until, but not inlcuding tools/dev/v8gen.py ...
  2. generate “debug” build files tools/dev/v8gen.py x64.debug
  3. change contents of v8/out.gn/x64.debug/args.gn to
    is_debug = true
    target_cpu = "x64"
    v8_enable_backtrace = true
    v8_enable_slow_dchecks = true
    v8_optimized_debug = false
    v8_monolithic = true
    v8_use_external_startup_data = false
    is_component_build = false

    needed to enable debugging

  4. compile with ninja -C out.gn/x64.debug
  5. compile debug version of samples/hello-world.cc with
    g++ -g -I. -Iinclude samples/hello-world.cc -o out.gn/x64.debug/hello_world -lv8 -lv8_libbase -lv8_libplatform -licuuc -licui18n -Lout.gn/x64.debug/ -pthread -std=c++0x

    -g enables debug version

  6. move into output directory pushd out.gn/x64.debug
  7. set library path and run LD_LIBRARY_PATH=./ ./hello_world
  8. return to v8 root popd


  1. configure: modify script/env for your setup
  2. build: ./scripts/build src/playground.cc
  3. run: ./scripts/run src/playground.cc
  4. build and run on change (dev): ./scripts/build-and-run-on-change src/playground.cc

vscode debugging

launch.json configuration

    "version": "0.2.0",
    "configurations": [
            "name": "(lldb) Launch",
            "type": "cppdbg",
            "request": "launch",
            "program": "${workspaceFolder}/out.gn/x64.debug/hello_world",
            "args": [],
            "stopAtEntry": false,
            "cwd": "${workspaceFolder}/out.gn/x64.debug",
            "environment": [{"name": "LD_LIBRARY_PATH", "value": "./"}],
            "externalConsole": true,
            "MIMode": "lldb"

${workspaceFolder} is v8 root directory