diff --git a/lib/db/build-index.js b/lib/db/build-index.js
index 1058296..c757261 100644
--- a/lib/db/build-index.js
+++ b/lib/db/build-index.js
@@ -10,6 +10,17 @@ module.exports = async function buildIndex (config, db) {
     const { type, project, detail } = evt
     let key = `${project.repoOwner}:${project.repoName}:${type}`
     switch (type) {
+      case 'PACKAGE_JSON':
+        if (detail.private) {
+          const prefix = `${project.repoOwner}:${project.repoName}:`
+          await db.batch([
+            { type: 'put', key, value: evt },
+            { type: 'del', key: `${prefix}PACKUMENT` },
+            { type: 'del', key: `${prefix}PACKAGE_MANIFEST` }
+          ])
+          continue
+        }
+        break
       case 'ISSUE':
         key += `:${detail.number}`
         break
diff --git a/test/build-index.js b/test/build-index.js
new file mode 100644
index 0000000..8de7e49
--- /dev/null
+++ b/test/build-index.js
@@ -0,0 +1,109 @@
+'use strict'
+const { suite, test, beforeEach, afterEach } = require('mocha')
+const assert = require('assert')
+const os = require('os')
+const path = require('path')
+const fs = require('fs-extra')
+const level = require('level')
+const github = require('../lib/github')
+const files = require('../lib/files')
+const npm = require('../lib/npm')
+const buildIndex = require('../lib/db/build-index')
+const { Project } = require('../lib/project')
+const indices = require('../template/indicies')
+
+suite('Private package indexing', () => {
+  let db
+  let directory
+  let pkg
+  let npmCalls
+  let restore
+  const prefix = 'example:sample:'
+
+  beforeEach(async () => {
+    directory = await fs.mkdtemp(path.join(os.tmpdir(), 'statusboard-index-'))
+    db = level(directory, { valueEncoding: 'json' })
+    pkg = { name: 'sample', version: '1.0.0' }
+    npmCalls = 0
+    restore = []
+    function stub (object, key, value) {
+      const original = object[key]
+      restore.push(() => { object[key] = original })
+      object[key] = value
+    }
+    stub(github, 'getRepo', async () => ({ branch: 'main' }))
+    for (const method of ['getRepoIssues', 'getRepoActivity', 'getRepoCommits']) {
+      stub(github, method, async function * () {})
+    }
+    stub(files, 'getPackageJson', async () => pkg)
+    stub(npm, 'getPackument', async () => {
+      npmCalls++
+      return { name: pkg.name, versions: { [pkg.version]: {} } }
+    })
+    stub(npm, 'getManifest', async () => {
+      npmCalls++
+      return { name: pkg.name, version: pkg.version }
+    })
+  })
+
+  afterEach(async () => {
+    for (const reset of restore) reset()
+    await db.close()
+    await fs.remove(directory)
+  })
+
+  function index () {
+    return buildIndex({
+      github: { token: 'unused-test-token' },
+      projects: [new Project('example/sample')],
+      orgs: []
+    }, db)
+  }
+
+  async function assertNoNpmMetadata () {
+    for (const type of ['PACKUMENT', 'PACKAGE_MANIFEST']) {
+      await assert.rejects(db.get(`${prefix}${type}`), err => err.notFound)
+    }
+    let projects
+    for await (const { key, value } of db.createReadStream()) {
+      projects = await indices.projects(projects, {}, key, value)
+    }
+    const project = projects.find(project => project.repo === 'example/sample')
+    assert.strictEqual(project.packageJson.private, true)
+    assert.strictEqual(project.packument, undefined)
+    assert.ok(project.repoDetails)
+  }
+
+  test('removes stale npm metadata when a public package becomes private', async () => {
+    await index()
+    assert.strictEqual(npmCalls, 2)
+    assert.ok(await db.get(`${prefix}PACKUMENT`))
+    assert.ok(await db.get(`${prefix}PACKAGE_MANIFEST`))
+    await db.put('example:other:PACKUMENT', { name: 'other' })
+
+    pkg.private = true
+    await index()
+    await assertNoNpmMetadata()
+    assert.strictEqual(npmCalls, 2)
+    assert.deepStrictEqual(await db.get('example:other:PACKUMENT'), { name: 'other' })
+
+    // Reindexing a private package should be safe after the records are gone.
+    await index()
+    await assertNoNpmMetadata()
+    assert.strictEqual(npmCalls, 2)
+
+    pkg.private = false
+    pkg.version = '2.0.0'
+    await index()
+    assert.strictEqual(npmCalls, 4)
+    assert.strictEqual((await db.get(`${prefix}PACKAGE_MANIFEST`)).detail.version, '2.0.0')
+    assert.ok((await db.get(`${prefix}PACKUMENT`)).detail.versions['2.0.0'])
+  })
+
+  test('indexes a new private package without fetching npm metadata', async () => {
+    pkg.private = true
+    await index()
+    await assertNoNpmMetadata()
+    assert.strictEqual(npmCalls, 0)
+  })
+})