Elixir That Ships
Production Elixir backends built on OTP principles — systems that handle the load, recover from failures, and give your team a codebase they can actually maintain.
Why Elixir
Built for the problems that keep you up at night
Elixir runs on the BEAM VM — the same runtime that powers Erlang systems with documented nine-nines uptime. When your architecture is built on supervision trees and OTP behaviors, outages stop being existential events and start being handled automatically.
Scale without re-architecture
Millions of lightweight BEAM processes run concurrently on a single node — no thread pools, no callback hell, no "we'll fix it when it breaks." Your system grows with your traffic, not despite it.
Failures that fix themselves
OTP supervision trees restart crashed processes in milliseconds. GenServer-based workers fail in isolation — a bad job doesn't take down your API. Your on-call engineer sleeps through incidents that would have woken them up on other stacks.
A codebase your team can own
Elixir's ecosystem is mature and growing — Fly.io runs on it, Discord scaled to millions of users with it, and the hiring market for Elixir engineers is stronger than ever. You're not betting on a niche.
Capabilities
What we build
We work across the full range of Elixir's strengths — from high-throughput APIs to stateful real-time systems where other stacks would demand expensive workarounds.
- High-volume API backends.
- REST and GraphQL services that handle traffic spikes without horizontal scaling gymnastics — because the BEAM was designed for concurrency from day one.
- Real-time collaborative features.
- Presence tracking, live dashboards, multiplayer state, and chat — built with Phoenix Channels and GenServers that hold user state in-process, not in Redis.
- Event-driven pipelines.
- Data ingestion, transformation, and streaming built with Broadway and GenStage — back-pressure included, no custom queue management required.
- Distributed systems and clustering.
- Multi-node BEAM clusters with libcluster, distributed Ecto, and pg-backed pub/sub — for when a single node isn't enough and you want distribution that the VM handles natively.
Why Cobalt Sentry
Experience meets modern delivery
- 20+ Years Shipping Software
- Elixir, Phoenix, Swift, and Astro in production. Not a generalist shop that Googles your stack after the contract is signed.
- Fixed-Price, No Surprises
- You know the cost before we write a line of code. No hourly billing, no scope creep invoices, no "we need another sprint."
- You Own Everything
- Full source code, deployment credentials, and documentation on handoff. No lock-in, no retainer required to keep the lights on.
Process
From consultation to production
We've built enough Elixir systems to know where projects go sideways. Our process is designed to surface that before a line of code is written.
- 1
Architecture first
We dig into your concurrency requirements, failure modes, and data flow before proposing a design. The right OTP supervision strategy on day one is cheaper than retrofitting it after launch.
- 2
Iterative builds with real visibility
Weekly demos, shared test coverage metrics, and code you can read. We write Elixir the way the community does — functional, explicit, with tests covering the behaviors that matter.
- 3
Handoff you can build on
Production deployment with observability configured — telemetry, structured logging, and health checks included. Plus 30 days of post-launch support and documentation written for the engineers who maintain it next.
Fixed-Price Elixir Development
Fixed-price projects, no hourly rates. Get a detailed quote tailored to your specific requirements.
Ready to get started?
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