Baremetrics alternative using Ruby

money_report.rb

# retrieve subscription data
########################

Stripe.api_key = ENV.fetch('STRIPE_SECRET_KEY')

subscriptions =
  Stripe::Subscription.list(status: 'all', limit: 100, expand: ['data.customer'])
    # Retrieve all subscriptions, following pagination until complete.
    .auto_paging_each
    .to_a
    # Filter out deleted customers.
    .filter { |s| !s.customer.deleted? }
    # Remove duplicate subscriptions per-customer. Keep the latest.
    .sort_by { |s| [s.customer.id, -s.created] }
    .uniq { |s| s.customer.id }

# calculate MRR
########################

paid_subscriptions = subscriptions.filter { |s| s.status == 'active' }
revenue_per_user = paid_subscriptions.map { |s| s.plan.amount.to_f * s.quantity / 100 }
monthly_recurring_revenue = revenue_per_user.sum(0.0)

# calculate ARR
########################

annual_run_rate = monthly_recurring_revenue * 12

# calculate ARPU
########################

average_revenue_per_user =
  revenue_per_user.sum(0.0) / revenue_per_user.size


# calculate conversion rate
########################

new_paid_subscriptions = paid_subscriptions.filter { |s| s.created >= 1.month.ago.to_i }
new_subscriptions = subscriptions.filter { |s| s.created >= 1.month.ago.to_i }
conversion_rate = new_paid_subscriptions.size.to_f / new_subscriptions.size * 100

# calculate churn rate
########################

canceled_subscriptions = subscriptions.filter { |s| s.status == 'canceled' }
churned_subscriptions =
  canceled_subscriptions
    # Select only recent cancelations.
    .filter { |s| s.canceled_at >= 1.month.ago.to_i || s.ended_at >= 1.month.ago.to_i }
    # Filter out customers who never added a payment method, i.e. an unconverted trial.
    .filter { |s| s.customer.default_source.present? }

paid_subscriptions_count_at_period_start =
  (paid_subscriptions.size - new_paid_subscriptions.size) + churned_subscriptions.size

churn_rate =
  churned_subscriptions.size.to_f / paid_subscriptions_count_at_period_start * 100

# calculate LTV
########################

converted_subscriptions =
  (paid_subscriptions + canceled_subscriptions)
    # Filter out canceled customers who never added a payment method.
    .filter { |s| s.customer.default_source.present? }

subscription_durations =
  converted_subscriptions
    .map { |s| ((s.ended_at || Time.now) - s.created) / 1.month }

average_subscription_duration =
  subscription_durations.sum(0.0) / subscription_durations.size
life_time_value =
  average_revenue_per_user * average_subscription_duration

# calculate revenue growth rate
########################

next_mrr = monthly_recurring_revenue
prev_mrr = (next_mrr - new_revenue) + lost_revenue
revenue_growth_rate =
  (next_mrr - prev_mrr) / prev_mrr * 100

# Time to Convert
########################

invoices =
  Stripe::Invoice.list(subscription: subscription.id, limit: 100)
    .auto_paging_each
    .to_a
# Sort invoices in ASC order, to make sure we can select their
# first paid invoice, not the most recent paid invoice.
sorted_invoices = invoices.sort_by { |i| i.created }

# Find their first paid invoice with an amount > 0.
first_paid_invoice = sorted_invoices.find { |i| i.amount_paid > 0 }

# Calculate the subscription's time-to-convert
time_to_convert =
  first_paid_invoice.status_transitions.paid_at - subscription.customer.created

source: https://keygen.sh/blog/how-i-replaced-baremetrics-and-chartmogul-with-rake/