gatsbyjs/gatsby · error

Installation of dependencies after initial scan is not imple

Error message

Installation of dependencies after initial scan is not implemented

What it means

gatsby-dev-cli watch scan: dependencies of a watched package changed (added/removed) after the initial scan, and installing new dependencies mid-watch is not implemented — the change log is printed but nothing is installed.

Source

Thrown at packages/gatsby-dev-cli/src/utils/check-deps-changes.js:170

        } else if (monorepoPKGjson.dependencies[key]) {
          acc.push(` - '${key}@${monorepoPKGjson.dependencies[key]}' was added`)
          needPublishing = true
        } else {
          acc.push(` - '${key}@${localPKGjson.dependencies[key]}' was removed`)
          // this doesn't need publishing really, so will skip this
        }
        return acc
      }, [])
      .join(`\n`)

    if (!isPublishing && depChangeLog.length > 0) {
      console.log(`Dependencies of '${packageName}' changed:\n${depChangeLog}`)
      if (isInitialScan) {
        console.log(
          `Will ${!needPublishing ? `not ` : ``}publish to local npm registry.`
        )
      } else {
        console.warn(
          `Installation of dependencies after initial scan is not implemented`
        )
      }
      return {
        didDepsChanged: needPublishing,
        packageNotInstalled,
      }
    }
  }
  return {
    didDepsChanged: false,
    packageNotInstalled,
  }
}

function getPackageVersion(packageName) {
  const projectPackageJson = JSON.parse(
    fs.readFileSync(`./package.json`, `utf-8`)

View on GitHub (pinned to e85d62f177)

Solutions

1. Manually install the newly added dependency in the consuming site
2. Restart the gatsby-dev watch process to pick up dependency changes

When it happens

Trigger: Thrown at packages/gatsby-dev-cli/src/utils/check-deps-changes.js:170 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of gatsbyjs/gatsby@e85d62f177 (2026-08-26). Data as JSON: /api/errors/8b143380ea43e07e. Report an issue: GitHub.