Many organizations start their FinOps journey by building homegrown tools. With engineering talent on hand, building a cost management solution in-house often seems faster and more flexible than evaluating third-party platforms. But as cloud environments grow in complexity, internal tools begin to show their limits. Maintenance burdens increase. Reporting gaps widen. And teams begin asking: Is it time to buy a purpose-built FinOps platform?
This post explores when it makes sense to shift from a homegrown tool to a purpose-built FinOps platform, and what the transition unlocks for your organization. We’ll also share insights from Ternary’s experience with companies navigating the build vs. buy decision.
Why organizations build in-house tools
Homegrown tools are usually born out of necessity. There are a variety of reasons why an organization may choose a do-it-yourself (DIY) approach:
- Immediate visibility. Teams need quick answers to foundational multi-cloud cost questions. By pulling data from native cloud tools, in-house solutions can provide a fast path to early insights.
- Custom logic and integrations. Proprietary chargeback rules, unique tagging structures, and internal billing systems often require bespoke configurations.
- Responsiveness. With engineering owning the tool, updates and changes can be made quickly without waiting on a vendor roadmap.
- Full control over data. Internal builds allow complete ownership of your data environment, including how security, access, and integrations are managed.
- Highly specific needs. In cases where no off-the-shelf solution meets your organization’s exact requirements, building internally can bridge the gap.
- Proof of concept. Internal tools can validate the value of FinOps and build internal momentum before committing to a platform investment.
For software companies, building internal tools can align with your business’s core competency. But for organizations outside of technology, including retail, healthcare, financial services, and others, DIY FinOps tool development can quickly become a distraction from your primary business goals.
Many teams underestimate how complex cloud cost management can become. What starts as a few scripts pulling billing data from native tools evolves into a sprawling system requiring constant updates for new SKUs, services, and pricing models.
Signs your homegrown tool has reached its limit
Here are the common signals marking when it’s time to consider buying a FinOps platform:
- Engineering drain. Engineers spend more time maintaining billing logic than delivering on core product features.
- Data delays or inaccuracies. Reports run slowly or are incomplete. Finance and product leads lose trust in the numbers.
- Missing core features. Anomaly detection, commitment-based discount tracking, or automated chargebacks remain out of reach.
- Hidden costs. Technical debt piles up. Key person risk increases. Burnout creeps in.
As noted by Tracy Woo, Principal Analyst at Forrester Research, DIY FinOps tooling efforts can require between 15 and 45 engineers to operate effectively.
For most organizations, that level of headcount is nearly impossible to justify from a total cost of ownership perspective. Unless you’re a company like Netflix, where infrastructure is truly a core competency, this level of investment is unsustainable.
When these patterns emerge, teams often start evaluating third-party FinOps platforms not as a cost center, but as a force multiplier.
What purpose-built FinOps platforms provide
FinOps platforms are specifically designed to address cross-functional requirements from the outset. The best platforms offer:
- Multi-cloud data normalization. Automated ingestion and real-time data updates across GCP, AWS, Azure, and more.
- Core FinOps capabilities. Custom dashboards, anomaly detection, forecasting, and cost allocation are must-haves.
- Enterprise-grade reliability. Vendors deliver support, security, uptime, and roadmap velocity that internal teams often can’t match.
- Extensibility. Platforms such as Ternary offer a “buy then build” approach, addressing more than 80% of needs immediately, and providing APIs for further development.
Real-world insights: The Linux Foundation
At the Linux Foundation, managing cloud costs across 12+ environments had become unmanageable via spreadsheets. By adopting Ternary, they enabled self-service FinOps at scale and reduced internal cloud cost-related inquiries by 30%.
When to make the switch
While each organization is unique, here are some common tipping points to consider:
- Cloud spend reaches $10M+
- Multi-cloud expansion adds operational complexity
- Too many engineers are dedicated to internal tooling vs. core business needs
- Teams struggle to meet audit, compliance, or forecasting needs
- Reporting lags are impacting decision-making
When the cost of delay exceeds the cost of licensing, the business case for buying a FinOps platform becomes clear.
Making the business case
Framing the platform investment correctly is key. FinOps isn’t about cutting costs. It’s about creating business value.
- Total cost of ownership (TCO): Factor in engineering time, errors, downtime, and opportunity cost.
- Return on investment (ROI): FinOps platforms can often pay for themselves through improved forecasting, commitment utilization, and anomaly detection.
- Strategic alignment: Unless software is your core business competency, it’s better to focus engineering efforts elsewhere.
Conclusion: Buy then build
Internal tools can serve as scaffolding, but they are not built to carry the weight of scale.
They can help teams begin their FinOps journey, but as complexity grows, scripts and spreadsheets fall short. At scale, organizations need purpose-built capabilities to manage cost visibility, optimization, and accountability effectively.
That is why the smartest path forward is not “build versus buy.” It is “buy then build.”
Buy a FinOps platform for the essentials, then extend it with APIs and custom workflows to meet the unique needs of your business. This way, your organization can invest in a smaller FinOps team that focuses on high-impact challenges instead of rebuilding what the third-party ecosystem already provides. The result is scalable cloud cost optimization without reinventing the wheel.
Ready to make the switch to Ternary?
