High-performance backend and API development

We build the system that supports your product: the business logic, the data, and the performance

We build backends and APIs for contexts where milliseconds matter: sports betting, fintech, and B2B SaaS. We deliver in short cycles, with automated tests, observability, and deployment from day one, and with the code and the documentation in your name. We also build the web interface and the iPhone and Android app.

Request the free 30-minute discovery call

Who it is for

  • You have a product or an internal system to build and you need someone who designs it, builds it, and answers for the result.
  • Your current system can’t take any more and you need a new backend or an integration that doesn’t fall over under real load.
  • You want to start with a bounded first version: the agile MVP is our fixed-price package by milestones, usually in six weeks.

It is not for you if…

  • the main challenge is visual or marketing, not business logic, data, or performance;
  • you are looking for a team by the hour without a defined scope;
  • you need a desktop application or a system outside our experience: we tell you on the first call.

What we build

  • Critical backends and APIs: REST or gRPC APIs for web and mobile; microservices or well-designed monoliths, depending on the case; real-time, low-latency processing.
  • B2B SaaS applications: complete web applications with Ruby on Rails or Go, with several customers on the same platform (multi-tenant) and integrated billing, ready to grow with Kubernetes and CI/CD.
  • Mobile apps: iPhone and Android apps from a single codebase (Flutter, or React Native if your team already uses it), connected to your API and published to the stores with your accounts, also for a system you already have.
  • High-performance tools and utilities: stand-alone programs and command-line tools in C++ or Rust for operations and automation.
  • Integrations and automation: connection with third-party services (Stripe, Twilio, and similar), migrations and data flows (ETL), webhooks, and event-driven architectures (RabbitMQ, Kafka) when they apply.

What we build it with

Modern C++ (17/20/23) for the most performance-demanding services; Go for microservices and web servers; Rust where memory safety and performance weigh equally; Ruby on Rails for B2B SaaS and fast product development; Flutter for mobile apps, or React Native if your team already uses it. Kubernetes, Docker, and infrastructure as code to deploy and scale; structured logs, metrics, and distributed traces to operate. The full list is in Who we are.

C++ Go Rust Ruby on Rails

How we build it

  1. Understand and plan. Requirements, constraints, architecture, and technologies; a written effort and timeline estimate.
  2. Build in iterations. One- or two-week cycles with a demo at the end of each; automated tests from day one and review of all the code.
  3. Deploy and operate. Early deployment to production, monitoring and alerts configured, technical documentation, and handover to your team.

It seems that perfection is attained not when there is nothing more to add, but when there is nothing more to take away.

Antoine de Saint-Exupéry, Terre des hommes (1939), chapter III, “L'Avion”. Source. Editorial version of the French original.
We look for the simplest solution that meets the goal and can be maintained. Every additional component must justify its cost and its usefulness.

Prior work on this kind of system

By members of the team that now runs SIMYL, before the company; we do not name companies or clients:

  • Cache and architecture for a betting API (in production since 2020; 2023 tests up to 100,000 requests per second): entry.
  • Property platform (2017): multi-tenant backend APIs for property and condo management, with contracts, payments, notifications, and reporting: entry.
  • Yardi to essensys migration (2017): without stopping the business or losing data: entry.
  • Remote-work monitoring (2014–2015): collector client and collector server in C++: entry.

Delivery commitments

  • Quality code: automated tests, code review, and CI/CD.
  • Documentation: technical and user documentation, updated with each agreed delivery.
  • Performance: we measure and optimize from day one, with the method in How we measure.
  • Security: good practices and dependency review in every delivery.
  • Maintainability: clean code, clear architecture, easy to extend.

How we start

  1. Free 30-minute discovery call: your product or system, what it must do, and its constraints.
  2. Technical proposal: architecture, technologies, owner, milestones, timeline, and price.
  3. Build: iterative, with demos and written decisions.
  4. Launch and handover: deployment, monitoring, documentation, and knowledge transfer.

Terms

A milestone project with written acceptance criteria or, if the scope is uncertain, time-based with a budget cap; stabilization included after delivery; the code and the intellectual property are yours, except SIMYL’s reusable components, which we license to you at no cost. All of it in How we work.

Request the discovery call or write to us at contact@simylresearch.com.