The Business …
David Okonkwo joined Stackline Labs as VP Finance when the company was at $4M ARR and growing fast. Stackline builds developer tooling for API infrastructure — $8M ARR now, 65 employees, Series A closed eight months ago with two tier-one VCs on the cap table who expect monthly reporting with zero tolerance for lateness or inaccuracy. The product is usage-based. Every customer pays based on API calls, data throughput, and active seats — a billing model that is enormously flexible for customers and enormously painful for finance.
▶ Sales Tools: Hubspot Enterprise
▶ Accounting: Netsuite
▶ Analytics: Baremetrics / Looker
▶ Team Size: 65
"I was the single point of failure for a billing model that invoiced $700K a month. That is not a finance function. That is a risk."
THE PROBLEM
Usage-based billing sounds simple. Customers pay for what they use. In practice it means David's finance team was pulling usage data from Snowflake every month, running it through a calculation model in spreadsheets, cross-referencing against contract terms in HubSpot, checking against what Metronome had already invoiced, reconciling the difference in NetSuite, and then — only then — generating the investor reporting pack.
Six days. Every month. For a Series A company whose investors expected reporting on the 5th.
The calculation model had grown organically as the product added new pricing tiers. Three people understood it. One of them had given notice. The month David realised he was the last person who fully understood how the model worked was the month he decided something had to change.
Investor reporting was always six days late. Billing disputes from customers who questioned their usage calculations were taking two weeks to resolve. And every month the spreadsheet got slightly more complicated and slightly more fragile.
What Carapace did …
Carapace connected HubSpot, NetSuite, Stripe, Metronome, and Snowflake and rebuilt the entire usage-based billing and reporting layer automatically.
Usage data flows from Snowflake into Carapace continuously. Every customer's consumption is calculated against their contract terms in HubSpot — automatically, in real time. Metronome invoices are cross-referenced against the calculation. Discrepancies are flagged before invoices go out. NetSuite is updated automatically when invoices are issued and when payments clear.
Investor reporting is generated automatically on the 1st of every month. MRR, ARR, net revenue retention, churn, expansion — all pulled from the connected sources, calculated against Stackline's defined metrics, and delivered to David and the board simultaneously. No manual assembly. No waiting.
Billing disputes went from two weeks to same-day — because every calculation is now documented and traceable back to the source data.
We were a Series A company sending investor reports six days late because one person understood our billing model. Carapace automated the entire thing. Reporting is same-day now. I actually sleep on the 1st of the month.
Same Day Delivery
Investor reporting went from six days late to same-day delivery. Usage-based billing is fully automated across 400+ customers. David is no longer the single point of failure for a $700K monthly billing operation.
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