Case Study
A fast-growing LATAM startup needed to replace its legacy infrastructure with a platform that could operate cost-effectively at scale. The business required automated, scalable processes to integrate with a wide range of national tax services — think Turbo Tax, but for their market. The existing system couldn't support the growth the company was experiencing. Every new customer added operational overhead, onboarding was slow, and infrastructure costs were growing proportionally with usage. The team needed a multi-tenant solution that would allow quick deployment of core infrastructure on customer accounts and dramatically faster onboarding — without rebuilding everything from scratch each time.A fast-growing LATAM startup needed to replace its legacy infrastructure with a platform that could operate cost-effectively at scale. The business required automated, scalable processes to integrate with a wide range of national tax services — think Turbo Tax, but for their market. The existing system couldn't support the growth the company was experiencing. Every new customer added operational overhead, onboarding was slow, and infrastructure costs were growing proportionally with usage. The team needed a multi-tenant solution that would allow quick deployment of core infrastructure on customer accounts and dramatically faster onboarding — without rebuilding everything from scratch each time.
Renaiss designed and built a cloud-native, serverless platform on AWS that replaced the legacy infrastructure with zero downtime. The architecture was multi-tenant from the ground up, enabling rapid deployment of core infrastructure on new customer accounts and dramatically faster onboarding.
Core functional components included user and admin authentication, payment gateway subscriptions, tax calculation and federal reporting, invoice issuance against federal systems, analytics, and automated alerts.
Full tech stack: AWS Lambda, DynamoDB, API Gateway, Cognito, SQS, SNS, SES, and S3 — orchestrated with Terraform and deployed through GitLab Pipelines, with a React frontend. Every component was chosen deliberately: Lambda eliminated always-on servers, DynamoDB handled variable workloads without performance degradation, and the SQS-driven architecture decoupled services so failures in one component didn't cascade across the system.
The impact was immediate and measurable. Infrastructure costs dropped 90% by eliminating idle server capacity and moving to a pay-per-use serverless model. The platform now supports more than 25,000 registered users and has processed over 200,000 invoices — numbers that would have stressed the previous architecture. And with CI/CD pipelines in place, the engineering team ships faster and with more confidence than before the migration.
A platform built to grow — handling tens of thousands of users without adding infrastructure complexity.
Federal tax reporting at scale, with the reliability that compliance-critical workflows demand.
Serverless means paying for what runs, not for what waits. The savings were structural, not incidental.
The legacy platform was replaced without interrupting service — no maintenance windows, no user impact.
The legacy platform was replaced without interrupting service — no maintenance windows, no user impact.
Auth, payments, tax calculation, invoice generation, analytics, and alerts — rebuilt cloud-native and production-ready.
Discovery & Architecture Design
We mapped the existing platform's dependencies, compliance requirements, and pain points to design a serverless architecture that could replace it without disruption.
Infrastructure as Code
We provisioned the entire AWS environment using Terraform — making the infrastructure reproducible, version-controlled, and ready to scale from day one.
Platform Rebuild
We provisioned the entire AWS environment using Terraform — making the infrastructure reproducible, version-controlled, and ready to scale from day one.
Zero Downtime Migration
We executed the cutover from legacy to cloud-native with no service interruption, managing data migration and traffic routing so users never noticed the switch.
CI/CD & Developer Experience
We implemented GitLab pipelines to automate testing and deployment, giving the team a modern release process and the velocity to keep iterating after go-live.
End-to-end platform, rebuilt from scratch
Auth, payments, tax calculation, invoice generation, analytics, and alerts — rebuilt cloud-native and production-ready.
Nearshore means hiring a tech team in a country geographically and culturally close to yours — typically within 1–3 time zones. For US companies, that means Latin America. You get real-time collaboration, overlapping work hours, and engineers who operate in English, without the communication friction that comes with offshore teams 10+ hours away.
We're based in Argentina — UTC-3. That means 4–5 hours ahead of the US West Coast and 2 hours ahead of the East Coast. In practice, we maintain a daily overlap of 4–6 hours with most US-based teams, which covers standups, code reviews, and real-time problem-solving without anyone working at midnight.
Our work sits at the intersection of cloud infrastructure, application architecture, and AI. Concretely: cloud-native architecture design, infrastructure automation, platform engineering, data pipelines, and GenAI integration. We don't do generic cloud support — we build and run systems that need to scale.
Our primary depth is in AWS. We also work with Azure and GCP depending on the client's existing stack — the goal is always to work within your environment, not to push a preferred vendor.
Yes — and it's one of the problems we work on most. App modernization usually means one or more of the following: breaking a monolith into services, re-platforming to cloud-native infrastructure, replacing outdated dependencies, or improving the CI/CD pipeline so your team can ship faster. We start with a technical assessment before recommending any approach.
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