Building software in phases: what comes first, how to prioritize and how to stay in control
Building software in phases means splitting the project into parts that work on their own, ordered by what hurts or pays off most. Each phase is tested and signed off before the next one starts, so you can pause, reorder or continue based on real use.
Building software in phases means splitting the project into parts that each work on their own, ordered by what hurts most or pays off most for your business. Every phase ends with something your team or your customers actually use, and it gets tested and signed off before the next one starts.
The alternative, ordering everything at once and waiting for delivery day, has one big flaw: you only find out what doesn't fit your business once it's all built. In phases, the project keeps correcting itself, because each step stands on what happened with the last one.
The one rule: every phase has to be useful on its own
Splitting a project into phases isn't the same as cutting it into pieces. “First the screens, then make them work” isn't two phases. The first half is useless until the second one shows up.
A good phase ends with something someone uses the next morning. Take software for a wholesale distributor: first, order taking, which pulls orders out of the text-message chaos; then inventory, which feeds off those orders; then a portal where customers order on their own. If the project stopped after phase one, you'd still be better off.
The first phase is usually what people call an MVP. I explain it in what is an MVP.
How to decide what goes first
When I order phases, I look at four things. They don't always weigh the same, but they're almost always enough to decide:
- What eats the most time today. If you lose hours every day writing quotes by hand, that beats a pretty report.
- What brings in money or customers. Customer-facing features (ordering, booking, quoting) usually pay off before internal ones.
- What other parts depend on. If inventory depends on orders, orders go first. There's a natural order, and fighting it costs you.
- What you're least sure about. If you don't know whether customers will use something, test it early and small, before building on top of it.
One project, split into phases
| Phase | What it includes | How you know it's done |
|---|---|---|
| 1. Orders | Regular customers order from their phone and you get a clean order | This week's orders came through the system, not voice notes |
| 2. Inventory | Each order updates stock and you see what needs restocking | You stopped counting by hand before confirming an order |
| 3. Customers and accounts | Each customer's history, their own price list and balance | You answer “what do I owe you?” without opening a spreadsheet |
| 4. Reports | Best sellers, customers who stopped ordering, how the month is going | You made a decision by looking at a report |
An example for a distributor. In your business, the phases and their order may look different.
How to stay in control without being technical
You don't need to know how it's built to keep the project on track. You need three things, and you ask for them at the start of every phase.
A plain-language list of what's included. Not “inventory module,” but “when I confirm an order, it comes off stock, and if something hits zero I get a heads-up.” That list is what you check against later.
Progress you can actually try. I share progress through a link: you open it on your phone, try it and tell me what you'd change. You don't wait until the end to see something.
A clear finish line. A phase is done when you've tried everything on the list and signed it off. Only then does the next one start. If something on the list doesn't work, it gets fixed inside that phase, not pushed forward.
If you're about to ask developers for quotes, how to request a software quote helps you get that level of detail.
What to do when you change your mind
You will change your mind, and that's fine. It's exactly why phases exist. What matters is where the change lands.
If it touches the current phase and it's small, it goes in. If it's big, write it down for the next phase and finish the current one as planned. Mixing the two is the fastest way to end up with a phase that never closes.
The good news is that new ideas almost always come from using the previous phase. Those are the best ones, because they come from what really happens in your business, not from what you pictured before starting.
One project, several pieces: Mecohue
For Mecohue, a pet store with a vet clinic and dog grooming in the Buenos Aires area, I built a website with a product catalog, services and WhatsApp booking, plus internal software with a cash register, appointments and one-tap WhatsApp reminders. They're separate pieces that solve separate problems.
Seen as phases, each one stands on its own: the website brings in customers even without the internal software, and the cash register organizes the counter even if appointments live somewhere else. That makes it easy to decide what goes first based on what the business needs most at that moment. You can see the site at mecohuepetshop.com.ar.
See the Mecohue caseHow we get started
On our first video call we write down everything you want, unfiltered. Then I propose how to split it into phases, in what order and why. I quote the first phase in detail and give you a rough idea of the rest, which we pin down when we get there.
If what you need is software to run the business day to day, see custom business management software. And if you're a manufacturer selling made-to-order products, I wrote about how I work with manufacturers.
Frequently asked questions
Does building in phases cost more than building everything at once?
It doesn't have to. What changes is how it's spread out: each phase gets its own quote, instead of committing to everything up front. And since you can stop after any phase, you never pay for something you already know you won't use.
Can I change the order of phases halfway through?
Yes, and that's one of the advantages. What you shouldn't change is the phase in progress; that one gets finished and signed off. Everything after it can be reordered based on what you learned from the previous phase.
What if I don't want to continue after the first phase?
You keep something that works and can be used on its own. That's the condition for every phase: it has to make sense even if it's the last one. If you want to pick it up again later, we continue from there.
If you have a big project and don't know where to start, tell me what you want to achieve and I'll suggest how to split it. Message me on WhatsApp at +54 9 11 6193-3176 or email contacto@facundocampo.com.ar. I answer in English and Spanish.