Support Facebook flow

Description

Contributor guide

Tech stack

javascriptnodejs

Domain

toolingbuild system

Issue type

feature

DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.

3

Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.

half day

Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.

stale

ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.

mostly clear

Prerequisites

Node.js basicsunderstanding of check build configuration

Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.

40

Research direction

First, examine existing checks in the check build repository to understand the pattern for adding new checks (e.g., ESLint, jshint). Then, explore how Flow's CLI can be used to validate JavaScript files with Flow type annotations. The issue requests integration so that check build runs Flow and reports errors. No PRs exist, so the implementation is open. Look at the lib/ structure and config handling to add a new check option.