Custom high availability architectures for platforms that simply cannot go down. From redundant database clusters and multi-region failover to observability and runbook discipline, we build around a concrete uptime target that suits your business case.
A high availability (HA) system is a platform designed so that a failure in a single component (a server, a data centre, a network link, a database replica) does not lead to a service outage for your end users. That sounds simple, but it affects every layer of your stack: how you write your application, how your database is set up, how your network routes traffic, how your deployments run, and how your team responds when something breaks at half past two in the morning.
We design and build high-availability systems for organisations where downtime immediately costs money or trust: payment providers, banks and insurers, telecoms, e-commerce platforms during peak moments such as Black Friday, healthcare providers with an EHR, government bodies delivering critical services, SaaS vendors with SLA obligations, and energy and logistics platforms that run around the clock. We always start from the same principle: the concrete uptime target, whether 99.9%, 99.99% or 99.999%, and work back to the architecture that delivers it. Not the other way round.
We work closely with your own DevOps or platform engineers, and with our DevOps-as-a-service if that function has not yet been established in-house. The designs we deliver land in code (Terraform, Pulumi, Kubernetes manifests) and in runbook discipline, not just in PDF reports that get forgotten in a Confluence folder.
Which one fits depends on where you stand today: a greenfield HA design, making an existing application HA-capable, or a complete multi-region or multi-cloud setup. In the first conversation we advise which option matches your availability target and budget.
For a new application or a replacement platform, we design the architecture around a chosen availability target. Multiple availability zones, stateless application services, a database cluster with automatic failover, a load balancer with health checks and circuit breakers, and a deployment pipeline that supports blue-green or canary releases. Everything is captured directly in infrastructure as code, so the whole environment is reproducible, whether by us, by you, or by a third party you bring in later.
You have a working application that currently runs on a single server, or that only comes back online after manual intervention when something fails. We analyse where the single points of failure sit — usually in the database, in stateful application components or in network routing — and address them step by step: database replication and automatic failover, moving sessions and state out of application services, placing a load balancer, adding a proper observability layer, and building the release pipeline that makes instant rollback possible.
For platforms where 99.99% or stricter is required and where the loss of an entire cloud region is a real risk. We build active-active or active-passive setups across multiple regions, with geo-DNS routing, cross-region data replication and a chaos engineering practice that periodically simulates regional outages. Often combined with cloud-native platform development and with edge computing for low latency on traffic arriving from different parts of the world.
A working, monitored and documented HA system that meets the uptime target we agree together — plus the runbooks, training and deployment pipeline your own team needs to run it.
Four patterns we repeatedly see among organisations that approach us for high-availability work. If you recognise one of them, we'd be happy to continue the conversation.
You run a payment platform, an order flow on a large e-commerce domain, a telecom service or an EHR that clinicians rely on in real time. Every minute of outage means rejected transactions, lost revenue, complaints or worse. A single-region, single-database setup is then a risk that no longer fits the volume or sensitivity of your business.
Your business customers, particularly larger corporates and government bodies, require 99.9% or 99.99% in the contract, with penalties for breaches. Your current platform doesn't consistently meet that, or it lacks the measurement and evidence layer needed to demonstrate compliance. An SLO-driven monitoring setup with error budgets closes that gap on both sides.
Black Friday, ticket sales, year-end closing in HR software, a media campaign: you face extreme spikes on top of a normal pattern, and you can't afford a capacity problem at exactly that moment. Auto-scaling, graceful degradation and separating critical from non-critical flows keep the entire application from collapsing under pressure.
DNB, the AFM, NEN 7510, BIO or a sector-specific standard requires you to demonstrate continuity of your services, with tested failover procedures and a documented disaster recovery (DR) plan. A paper plan without a tested implementation no longer constitutes valid evidence. We link the design to periodic DR drills that do provide proof, often in combination with an ISO 27001 project.
With OneDayBuild, we turn your idea into something tangible in one day for €1,150, so you can see whether further development is worth the investment. Decide to go ahead with the full build? Then we credit the full cost.
Explore OneDayBuild →A conversation in which we establish which flows in your platform are truly mission-critical, which can afford some downtime, and which uptime target suits them. Not every flow needs 99.99%; some need more. We also map what your current measurement and monitoring layer already shows, which is usually the best starting point for the design.
A short discovery phase in which we test the current architecture against your uptime target: where are the single points of failure, where is state that we would rather no longer tie to a single node, how does database replication stand, and what does the network path look like? At the end you receive a concrete blueprint, a sprint plan and a prioritisation of the changes with the greatest impact.
We work in two-week sprints and deliver a working, production-tested improvement every sprint. We often start with the observability layer, since without measurement you can't tell whether an intervention helps, and then work through the database layer, the application layer and the deployment pipeline. Our engineers pair with your own platform engineers where they exist; knowledge transfer is built into every sprint rather than left until the end.
After go-live, we plan the first DR drill: we simulate a targeted failure in a production-like environment and check whether failover, observability and runbooks do what they promised. We then join a chaos engineering cadence and post-mortems of real incidents, so the architecture and runbooks keep improving rather than slowly eroding. Where needed, we also work on a separate disaster recovery platform for disaster recovery.
The questions platform owners, IT managers and CTOs usually ask us before a project begins.
A free, no-obligation half-hour introductory call. We listen to which flows are mission-critical, to your current architecture, and to the uptime target that suits your business, and we give direction you can use straight away, even if we ultimately don't work together.
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