Track Medium Follower Growth and Social Graph Snapshots

Follower count is vanity. Useful products measure velocity, who follows whom, and superfans on hit posts.

Tool outcome: A medium_social_snapshots table + one SQL query for week-over-week growth.

What to measure

Metric	Endpoint	Use
Follower velocity	`/user/{id}` + weekly snapshot	Creator dashboards
Following graph	`/user/{id}/following`	Discovery (“who do they read?”)
Superfans	`/article/{id}/fans`	Outreach lists

Snapshot job (pseudo-ETL)

const API = 'https://api.zenndra.com';
const headers = { Authorization: `Bearer ${process.env.ZENNDRA_API_KEY}` };

async function snapshotUser(userId) {
  const profile = await fetch(`${API}/user/${userId}`, { headers }).then((r) => r.json());
  const followers = await fetch(`${API}/user/${userId}/followers`, { headers }).then((r) => r.json());

  await db.query(
    `INSERT INTO medium_social_snapshots (user_id, captured_at, followers_count, following_count, sample_follower_ids)
     VALUES ($1, NOW(), $2, $3, $4)`,
    [
      userId,
      profile.followers_count,
      profile.following_count,
      JSON.stringify((followers.users ?? []).slice(0, 50).map((u) => u.user_id)),
    ]
  );
}

Run weekly—not hourly—to respect rate limits and because trends are slow-moving.

SQL: week-over-week growth

SELECT
  user_id,
  captured_at::date,
  followers_count,
  followers_count - LAG(followers_count) OVER (PARTITION BY user_id ORDER BY captured_at) AS delta
FROM medium_social_snapshots
ORDER BY user_id, captured_at DESC;