Cian-OS Playbooks Deciding what to build
Build, Buy, Automate—or Use AI?
In short
AI is one branch of the decision tree, not the default answer. Every need has six possible outcomes — build, buy, automate, use AI, change the process, or not yet — and eight questions that separate them: differentiation, available software, process stability, rate of change, judgment required, data, integrations and risk.
When a company decides to “do something with AI,” the underlying question is rarely about AI. It’s the same question businesses have asked about every technology for decades: is this need best solved by building, buying, automating — or by changing the way the work gets done? AI added a branch to that tree. It didn’t replace it. This guide lays out the six possible outcomes and the eight questions that separate them.
Why AI isn’t the default answer
AI is the best tool for one specific kind of problem: decisions that require interpreting ambiguous information, based on patterns a rule can’t capture, with enough data and someone who can verify the output. Outside that territory it tends to be the most expensive option, the least predictable and the hardest to audit.
That’s why starting from “where can we use AI?” gets the order backwards. The useful order is: the need first, then the questions, and the outcome last — whatever it turns out to be.
The six possible outcomes
- Build: your own software, when the capability is part of how you compete and no product handles it the way it needs to.
- Buy: an existing product, configured and integrated, when the capability doesn’t differentiate.
- Automate: let a system run repetitive steps with clear rules, on top of a stable process.
- Use AI: a model that supports — or makes — decisions that require judgment, with data and verification.
- Change the process: remove steps, clarify ownership or eliminate duplicated information, sometimes without writing a line of code.
- Not yet: wait until the data, the owner or the stability the decision needs actually exists.
Outcomes combine. A need can end up as “change the process, then buy,” or “build, with AI in one specific step.” What matters is that every part of the answer has a reason behind it.
The eight questions that separate them
| Criterion | Question | If yes… | If no… |
|---|---|---|---|
| Differentiation | Is it part of how you compete? | Leans toward build | Leans toward buy |
| Available software | Does a product cover most of the process? | Buy and integrate | Build, or simplify |
| Process stability | Does it run the same way every time? | Automate | Change the process first |
| Rate of change | Do the rules change often? | Something the business can configure | Fixed rules |
| Judgment required | Does it involve interpreting ambiguous information? | An AI candidate | Rules, no AI |
| Data | Is there enough reliable history? | AI is viable | Not yet — or data first |
| Integration complexity | Must it read and write across several systems? | The cost is in the integrations | Buying or automating is simpler |
| Risk | Would a mistake be costly or hard to detect? | Human decision and controls | More automation, sampled review |
There are no weights or scores. No question decides on its own, and adding up answers hides the one that matters most: if the risk is high, no number of “yes” answers on the other seven justifies taking people out of the decision.
How the answers combine
Some patterns come up often enough to be worth recognizing:
It doesn’t differentiate, and a product exists
Buy it. Building what the market already sells — accounting, payroll, a standard CRM — is rarely an advantage; it’s a maintenance cost nobody budgeted for. The real work is integrating it well and not bending the process to fit it.
The process is unstable
No technology fixes a process that changes depending on who runs it. Automating it locks in its errors; buying software to hold it up just makes them more expensive. Change the process first, then pick the tool.
There’s judgment, but no data
The need is a good AI candidate, but it isn’t viable today. The honest outcome is “not yet,” with a concrete task attached: start recording, reliably, the information a model would need. Often that record alone solves a good part of the problem.
There’s judgment, data, and an expensive mistake
Use AI as support, not as a replacement: the model estimates, recommends or ranks, and a person decides. The AI lives inside the workflow where the decision gets made — not in a separate tool nobody opens.
The capability differentiates, and nobody sells it
Build — but only the part that differentiates. Around almost any custom system there are standard pieces — authentication, payments, email, reporting — that are better bought.
An illustrative example
A field-services company (an illustrative example, not a client) runs three needs through the eight questions:
| Need | What the questions said | Outcome |
|---|---|---|
| Billing and collections | Doesn’t differentiate; mature products exist; stable rules | Buy, and integrate with the work-order system |
| Assigning technicians to visits | Differentiates (it’s their service promise); no product respects their zone and specialty rules | Build, with rules operations can edit |
| Classifying incoming requests | Requires interpreting free text; years of classified history; a mistake gets caught at the next review | Use AI to suggest the category, with human confirmation |
Three needs, three different outcomes, and only one uses AI. The company didn’t adopt “an AI strategy.” It made three decisions with the same discipline.
A real case: AI inside the workflow where the decision happens
Prenda Crédito Avanza is a lender in Guatemala that has run on the platform it built with Ciancoders since 2018. Assessing the risk of each application consistently took judgment — and the information needed already lived in the platform: every application and how it turned out. In late 2022, an AI model that estimates the risk of each application was added inside the existing approval workflow, rather than as a parallel tool. The final decision still belongs to the credit team. The written-off portfolio fell 19%, and the delinquent portfolio fell 8%.
That project didn’t come out of applying this matrix. We show it because it meets the conditions of the “use AI” branch: judgment required, reliable historical data, an expensive mistake, and a person who still makes the call.
Common mistakes
- Asking “where can we use AI?” instead of “what does this part of the business need?”
- Building out of pride something the market already solves better and cheaper.
- Buying to avoid deciding, then bending the process until the product fits.
- Automating a process nobody has reviewed.
- Comparing products by features and ignoring the cost of integrating them.
- Taking people out of an expensive decision because the model is “almost always right.”
- Reading “not yet” as failure, when it’s a list of conditions and a date to look again.
Practical tool · Decision matrix
Decision matrix: build, buy, automate or use AI
One need at a time. Answer every question with evidence, not preference. No single answer decides — the pattern does, and the final record writes down why.
A · The eight questions
| Criterion | Question | If yes, it points to… | If no, it points to… |
|---|---|---|---|
| Differentiation | Is this capability part of how your company competes or stands out? | Build: it’s an asset you own. | Buy: what doesn’t differentiate rarely justifies your own software. |
| Available software | Is there a product that covers most of the process the way it needs to work? | Buy, configure and integrate. | Build — or simplify the process until a product fits. |
| Process stability | Is the process defined, and does it run the same way every time? | Automate it, or build on it. | Change the process first: automating an unstable process locks in its errors. |
| Rate of change | Do the rules change often (pricing, regulation, criteria)? | Something the business can configure, bought or built. | Fixed rules: automation is straightforward. |
| Judgment required | Does each case require interpreting ambiguous information — text, documents, patterns — that a rule can’t capture? | An AI candidate, with human verification. | Rules-based software or automation: AI would add cost and uncertainty. |
| Data | Is there enough reliable, accessible historical data for what you want to decide or predict? | AI is viable. | Not yet — or data first. |
| Integration complexity | Does the solution need to read from and write to several existing systems? | The real cost is in the integrations: compare those before features. | Buying or automating is simpler. |
| Risk | Would a mistake be costly, regulated or hard to detect? | Human decision, controls and traceability; AI as support. | You can automate more and review by sampling. |
B · The six outcomes
| Outcome | When it fits | Warning sign |
|---|---|---|
| Build | The capability differentiates, no product fits, and the company can sustain the software over time. | Building what the market already sells better, or something nobody will maintain. |
| Buy | The capability doesn’t differentiate and a product covers most of the process. | Bending the process to fit the product, or underestimating integrations and licenses. |
| Automate | The process is stable and repetitive, with clear rules. | Automating a process nobody has reviewed: the errors just come out faster. |
| Use AI | There’s judgment a rule can’t capture, enough data, and someone to verify the output. | Using AI where a rule was enough, or with no way to know when it’s wrong. |
| Change the process | The problem is how the work gets done: extra steps, unclear ownership, duplicated information. | Buying or building software to prop up a process that should go away. |
| Not yet | Data, ownership, stability or a success metric is missing. | Treating it as a permanent no instead of a list of conditions. |
C · The matrix
Need under review: ______________________________________________
| Criterion | Answer (yes / no / unsure) | Evidence | Points to |
|---|---|---|---|
| Differentiation | |||
| Available software | |||
| Process stability | |||
| Rate of change | |||
| Judgment required | |||
| Data | |||
| Integration complexity | |||
| Risk |
D · Decision record
| Field | Answer |
|---|---|
| Decision (one of the six outcomes) | |
| The answers that weighed most | |
| What we ruled out, and why | |
| What would have to change to revisit it | |
| Owner and review date |
How it connects to Cian-OS
In Cian-OS, “build or buy” belongs to Foundation — the system where product, architecture, data and security decisions get made before anything accelerates. But it only gets answered well if Intent has already fixed the business outcome you’re after: without that metric, every outcome looks reasonable.
In a real case
Financial services · GuatemalaPrenda Crédito Avanza−19% written-off portfolioRead the full caseAI Opportunity Assessment
If you’d like to run this exercise with us, the AI Opportunity Assessment turns it into a prioritized Opportunity Map, with a brief per opportunity and one concrete first step.