Backend and API development in Miami
A Miami fintech backend is usually a ledger with an API around it, whether or not anyone called it that at the start. Money arrives through one provider, leaves through another, and the two report back on different schedules in different formats. The failures that hurt are quiet ones: a webhook retried twice that credits an account twice, a settlement file that does not match and nobody notices for a week.
We build and repair those backends in Node and Python on PostgreSQL. Every payment call is idempotent, every balance change is an entry that can be traced to the event that caused it, and reconciliation against your partner's files runs on a schedule and tells someone when it disagrees. If the backend already exists, we start by writing down where the money can go missing, then fix those paths first.
Miami's software buyers tend to face south. Many of the companies that set up here in the last few years came for the same reason: it is where a US-incorporated business can sit next to its Latin American customers, investors and staff. Cross-border payments, remittances, neobanks, crypto infrastructure and the US arms of Latin American companies make up a large part of the local technology market, alongside real estate, hospitality and trade. The systems they need are rarely built for one country.
That shapes the work. Money movement is the core of the product rather than a feature bolted onto it: idempotent payment calls, a double-entry ledger, reconciliation jobs that compare your records against a partner's settlement file every night and flag the difference. The product has to handle Spanish and Brazilian Portuguese properly, validate local ID numbers and address formats, and settle through rails such as Pix in Brazil and SPEI in Mexico as well as cards. Crypto products add wallets, chain indexers and custody integrations, and the same principle applies: your database has to agree with the chain, and when it drifts, somebody needs a report saying where. Real estate, hospitality and trade bring their own version of the problem, usually a workbook that runs the business and quietly disagrees with its copies.
The hiring market has moved with the migration of finance and technology firms from New York and California. Built In puts the average base salary for a software engineer in Miami at around $145,000, and engineers who are bilingual and have shipped payments work are the hardest seat to fill. That is the seat we fill for a defined build: a payments integration, a reconciliation system, a second-country launch, or the months while a permanent hire is found. Work starts with a fixed-price two-week piece, and the code belongs to you from the first commit.
We move our working day for Florida. Four hours of every working day overlap with your morning in Eastern time, stand-up included, so calls, code review and decisions happen live with the engineer who writes the code. Everything else is written down where you already work, and runbooks and architecture notes are written as we go, so the next engineer who joins can read how the money moves.
We are the right fit for a defined build: a payments integration, a reconciliation system, a second-country launch. Senior capacity starts within days, the first piece is a fixed-price two-week engagement, and we can cover the months while a permanent hire is found. Agencies serving Miami's fintech, hospitality and retail brands can put the work under their own name.
Four ways this arrives.
We read the code, write down what it does versus what everyone believes it does, and give you the list of the five things most likely to page someone at night. Then we fix those first.
Usually queries, not architecture. We profile under real traffic, fix the plans and the indexes, and only then discuss whether anything needs splitting apart.
A mobile client, a partner integration, a public API. We design the contract first, version it properly, and write the docs your consumers will read.
Jobs that silently vanish, retries that duplicate charges, a queue nobody monitors. We make it idempotent, observable, and boring.
A moderated messaging backend where sends acknowledge in-band and the review runs behind them.
Read the write-up →Asked by Miami teams.
How do you work with teams in Miami?+
We are in Bengaluru and move our working day for Florida, so four hours of every working day overlap with your morning in Eastern time, stand-up included. Calls, code review and decisions happen in that window. Everything else is written down in your own tools, whether that is Slack, GitHub or Linear, and the person on every call is the engineer who writes the code.
Can you build for Latin American markets as well as the US?+
Yes, and it is more than translation. Mexican and Argentinian Spanish differ, Brazilian Portuguese is its own language, and ID numbers, address formats, currencies and instalment payments all change by country. We design localisation into the first component, format money through the platform's own internationalisation tools, and integrate the payments provider you have chosen, with room for a second provider and local rails such as Pix and SPEI.
How does your rate compare to hiring in Miami?+
Built In puts the average base salary for a software engineer in Miami at about $145,000, before equity and benefits. Our published rate is $35/hour, or $5,400 a month for an embedded engineer, with a $5,000 minimum. There is no recruiting time and no employment overhead, and work starts within days of the call. The first piece is a fixed-price two-week engagement at $2,800, so you judge us on working code.
Can you work white-label for a Miami agency?+
Yes. Miami agencies regularly win fintech, hospitality and ecommerce projects that need more engineering than the in-house team can take on at once. We work under your name as part of your team, so your client deals with you and the work arrives as yours. The NDA comes before any specifics, the code belongs to the client from the first commit, and runbooks and architecture notes are written as we go.
Can you work in our existing codebase?+
Yes, and it is most of what we do. We do not require a rewrite as a condition of working with you. If we think a rewrite is genuinely the right call we will say so, with the reasoning and the cost, and you can decide.
What if the backend is in a language you do not list?+
Then we will tell you. We are useful in Node, Python and TypeScript. We can read Go and PHP well enough to migrate off them. We would not take a Rust or Elixir project and learn it on your budget.
Do you write tests?+
For anything with money, permissions or data loss in it, yes. We do not chase a coverage number. We will tell you which parts are covered and which are not in the handover notes.
Who owns the code?+
You do, from the first commit. Repositories live in your organisation. If we set them up, we transfer them before the first invoice.
What happens when the engagement ends?+
You get runbooks, architecture notes and a recorded walkthrough. We stay available for questions for a month at no cost, because a handover that needs us on retainer is not a handover.