In many organizations I’ve worked with, the process starts the same way. Product wants to build a new feature, expected usage is estimated, and engineering is asked how it can be delivered. The discussion focuses on feasibility, timelines, and scale. Cost rarely enters the conversation, unless a new vendor or service requires a contract to be signed.
Even in those cases, cost is usually examined only during contract negotiation. After that, as development moves forward, cost tends to disappear from day-to-day discussions. Leadership may understand the expected revenue or business impact of a new feature, but without cost being tracked, it’s difficult to know whether that feature is actually paying off.
The problem is that many of the decisions that ultimately shape cost don’t happen during contract negotiation. They happen later, during design and implementation, as systems evolve and more teams build on top of them. Once a tool or service is approved, engineers use it in ways that make technical sense, without visibility into how small design choices increase cost over time.
This is where things tend to break down. Costs don’t show up during design or rollout, they appear later, once the change is live and usage starts to grow. By then, the system is already running in production and it will be expensive to adjust. Leadership is left choosing between living with the spend or funding a separate effort to clean up decisions made without cost in mind. From that moment on, cost control is reactive, not intentional.
A common pattern: approved tools, invisible cost
I’ve seen this pattern repeat across different organizations and contexts, and almost never because someone made a “bad” technical call. The issue usually starts earlier, with tools that were approved once and then quietly became defaults.
In one case, a caching layer was added to protect a critical service during database outages. The team chose the same cache technology already used in other services, which made it quick and easy to onboard. In another case, a director, worried about potential hiccups during a major conference, asked the team to overprovision the database to be on the safe side, without really thinking about cost. Both decisions went through normal reviews, made sense at the time, and shipped without raising red flags.
What no one stopped to ask was a simple question: how do these services actually charge us?
In the caching case, the organization paid for managed instances across multiple regions even though the cache was rarely used. In the database case, the extra capacity ended up not being needed at all. If it had been clear upfront that these decisions would drive costs up, a different approach would almost certainly have been taken.
The cost only became obvious much later, once the systems had been running in production for a while. By then, the money was already spent and there was no easy way back. Sometimes this meant accepting the cost. Other times, it led to disruptive changes to undo decisions that would have looked very different if cost had been visible earlier.
Looking back, the decisions made sense. The problem was that the organization had no way to see the financial impact of those choices while they were still easy to change.
Bringing cost into engineering decisions
These examples make one thing clear: if cost isn’t visible where decisions happen, it won’t be part of those decisions.
Fixing this doesn’t require turning engineers into finance experts. It requires putting cost information in the right place, at the right time, so it becomes part of how decisions are made.
The sections below break this down into three practical shifts: bringing cost into design conversations, defining cost in unit metrics that teams can actually reason about, and keeping cost visible once systems are live.
Treat cost as a non-functional requirement
One of the simplest ways to bring cost into engineering decisions is to treat it as a non-functional requirement. Design documents, RFCs, and architecture reviews should include a required cost section as part of the organization’s standard templates.
That section doesn’t need detailed estimates. Its purpose is to cover the basics: what drives cost in this design, how cost changes as traffic or data grows, and which alternatives were considered. Even rough estimates are often enough to flag designs that could become expensive at scale.
Making cost a required part of these documents ensures it’s discussed early, while decisions are still easy to change. It sets a clear expectation that cost matters during design and prompts reviewers to ask the right questions before decisions are finalized.
Define cost as a unit metric
Once cost shows up in design templates, the next step is making it something the organization can actually reason about. Instead of thinking about cost only as a project estimate, engineering teams should be able to see what it really costs to run the systems they own.
A practical way to do this is to track cost in terms people already understand. That could be cost per payment attempt, cost per hotel booking, cost per user action, or any other unit that reflects how the system is actually used. With this kind of visibility, design templates stop being a formality and start being useful. Teams can reason about the cost impact of a change while decisions are still being made, not after the fact.
This also changes the conversation between engineering and product. Product teams can better judge whether a new feature is likely to be profitable. Engineering can point out when a small technical change has a large effect on the cost of each transaction. Over time, it becomes easier to spot features that are expensive to operate but don’t deliver enough value to justify further investment.
None of this needs to be accurate. Even rough numbers are useful. What matters is that cost becomes visible at the same level where product and engineering already make decisions, instead of showing up later as an unpleasant surprise in a financial report.
Make cost visible at the right organizational level
Once a system is live, the cost doesn’t stay still. Traffic grows, usage changes, and new features get added. That’s why cost can’t live only with finance or show up in the occasional review. It needs to show up in the same dashboards and metrics teams already use to run systems day to day.
Visibility alone isn’t enough. When cost is only visible at a company level, people don’t have clear ownership or incentives to optimize it. Making cost visible at the level of services or domains ties it to concrete responsibility and gives teams a reason to act.
This only works if the basics are in place. Resources and API usage need to be properly tagged, and those tags need to flow into the dashboards teams already check every day. When cost is tied to the systems teams own and shows up where they do their work, reducing spend stops feeling abstract and starts feeling like part of running the system.
Final thoughts
Every architectural choice has a cost, whether it’s discussed or ignored. When cost isn’t visible early, systems don’t become expensive because of reckless decisions, but because reasonable tradeoffs were made without full context. By the time finance flags the issue, the system is already widely used and hard to change.
Bringing cost into engineering changes that. It makes cost something teams consider while making decisions, not something they react to later. This isn’t about adding more approvals or tightening budgets. It’s about giving the people making technical choices the visibility they need to understand financial impact before those choices are locked into production.
When budgets go off track, it’s easy to blame spending. Harder, but often more useful, is asking whether the right people could see the cost in the first place.
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