Startup team Forestwalk Labs swapped GitHub Actions for YC‑backed Blacksmith after CI runs lagged. Blacksmith promised a drop‑in replacement that ran faster and, on the free trial, seemed cheaper. Importing the existing workflow was painless, and the first builds hit the machine in half the time.

Soon the free‑minute quota hit 80 %. Blacksmith sent an email warning that a credit card was needed to avoid "disruption." The team kept coding, assuming the warning was about suspicious activity. Weeks later, an invoice for $1,081.45 appeared, followed by an overdue notice that the bill was already due.

Blacksmith’s support later clarified that the warning referred to account flagging, not job termination, and that overages accrue at published rates even without a card. The company admitted the billing confusion could be a growth‑hacking tactic or simple oversight, promising future mitigation.

Despite the surprise invoice, Forestwalk Labs weighed the trade‑off: Blacksmith cuts CI bottlenecks by 50 % faster than GitHub Actions, while the free tier’s hidden cost can reach $1,081 if unmonitored. The team will likely stay if they pay, but the episode warns other startups to monitor trial limits closely.