Company Background

Blacksmith (YC W24) entered the market with a mission to build the fastest infrastructure for software development.

The company provides high-performance CI/CD services that complement GitHub Actions. By avoiding hyperscalers and running on bare metal infrastructure, Blacksmith delivers faster, more cost-effective and more reliable CI for developers.

Blacksmith raised $3.5 million in seed funding, then closed a $10 million Series A led by Google Ventures just four months later (with the later round closing in just 14 days).

Blacksmith gained over 700 paying customers in year one alone and now boasts eight figures in ARR. Notable customers include Ashby, Chroma, Clerk, Devsisters, Mintlify, Slope, Supabase and VEED.

We're proud to partner with such an amazing infrastructure tool.

The Challenge

As a scaling infrastructure company, Blacksmith needed a billing system that could match both their technical complexity and usage-based pricing with multiple variables. Their GitHub Actions-based service required precise usage tracking and flexibility for usage-based pricing, enterprise overrides, add-ons and support for different types of architecture, which creates a complex pricing matrix.

As former infrastructure engineers at companies like Cockroach Labs, they understood the complexity and opportunity cost of building and maintaining an in-house billing system.

With Blacksmith's fast growth and diverse usage patterns across their customer base, Blacksmith needed a solution that could scale with them and wouldn't require renewed engineering effort if they wanted to experiment with pricing. Manual billing processes or rigid SaaS tools wouldn't support their go-to-market velocity or technical requirements.

Why Lago

Lago is API-first infrastructure that integrated seamlessly with their existing stack. As a developer-focused company (and a developer-heavy team), they needed dev-friendly tooling their engineering team could implement and be confident in using for a long time.

Lago's open-source nature gives Blacksmith direct visibility into their billing engine as well as the ability to customize. This transparency was key in building confidence in choosing Lago as their billing infrastructure.

Lago's support for usage-based billing models was essential for Blacksmith's compute-intensive service. The platform's ability to handle complex metering and aggregation matched the sophistication of their own infrastructure offerings.

The speed of implementation was crucial for a fast-moving startup. Lago's API-first design allowed Blacksmith to integrate billing capabilities without derailing their product roadmap, blocking product launches to ship new pricing/monetization or diverting engineering resources away from core development work.

Expected Outcomes

Since going live in January 2025, Blacksmith has established a scalable foundation for billing operations. The team can now focus engineering resources on improving CI performance rather than maintaining billing infrastructure.

The company expects to support continued growth with automated, scalable and accurate billing for their expanding customer base. As they add new pricing tiers and compute options, Lago provides the flexibility to iterate quickly on go-to-market strategies.

Blacksmith aims to maintain their developer-friendly approach to pricing while ensuring accurate metering. The billing system supports their mission to make fast CI accessible to teams of all sizes.

The team anticipates that reliable billing infrastructure will support their path to significant scale as they continue serving the growing market of AI and developer tool companies that demand high-performance CI/CD.