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Web Application Development in Seattle & beyond

We architect production-grade web applications from first commit to launch, with clean codebases, sensible patterns, and the test coverage to keep moving fast for years.

Most product teams don't fail because they picked the wrong framework. They fail because the codebase becomes hostile to change six months in. We build web applications that stay pleasant to work in years after launch: clear domain models, thin controllers, fat services, and tests that document intent rather than implementation.

We've shipped multi-tenant SaaS platforms, marketplaces, internal tools, and customer portals. Our default stack today is React 19 + TypeScript on TanStack Start, server-rendered, containerized, and portable to any host, and we still maintain and extend the Rails and Node systems we've built over the years. Every engagement starts with a written architectural plan you own, even if you take it elsewhere.

What is custom web application development?

A custom web application is software built for your specific workflow rather than adapted from an off-the-shelf product: customer portals, booking and scheduling systems, marketplaces, dashboards, and internal tools. Where a website presents information, a web application does work: it has logged-in users, data that changes by the minute, and business rules no template anticipates.

The build-vs-buy line is simpler than it looks: if an existing SaaS covers 80% of your workflow, buy it. Build custom when the remaining 20% is where your business makes its money. That gap is what custom development exists to close.

Who can build my app in Seattle?

If you're looking for a Seattle software development partner who can take an idea from napkin to production, that's the engagement we run: a paid discovery sprint produces a written plan and fixed quote, then two-week sprints deliver a deployed, testable build every Friday. You own the code, the infrastructure, and the plan from day one, whether you continue with us or take it in-house.

What's included

  • React 19 + TanStack Start front-ends
  • Node & TypeScript back-ends
  • API design (REST, GraphQL)
  • Test coverage & CI/CD pipelines

Ideal for

  • Founders launching a v1 that needs to survive contact with real users
  • Teams replatforming a legacy app without a 12-month rewrite
  • Companies extending an existing product with a new module or API
  • Operations teams that have outgrown their spreadsheets

How we work

  1. 1

    Discovery sprint

    1-2 weeks of paid discovery: workshops, technical spike, and a written plan with scope, sequencing, risks, and a fixed quote.

  2. 2

    Foundations

    Repo, CI/CD, environments, auth, and the first vertical slice through the stack, deployed to staging in week one.

  3. 3

    Iterative build

    Two-week sprints, demoable Friday builds, and a running staging environment your team can poke at any time.

  4. 4

    Launch & stabilize

    Performance hardening, observability, runbooks, and a 30-day window where we watch your alerts alongside you.

What you'll get

  • Architectural decision records (ADRs) for every major choice
  • Production-ready application with CI/CD, monitoring, and runbooks
  • Test suite (unit, integration, system) with meaningful coverage
  • API documentation and a Postman / OpenAPI collection where relevant
  • Handoff sessions and a 30-day stabilization window

Related work

FAQ

What's your default stack?
React 19 + TypeScript on TanStack Start: server-rendered for SEO, one language across the whole codebase, deployed as a Docker container behind Caddy on your infrastructure or ours. We also maintain and extend existing Rails and Node applications, so working with us doesn't mean a rewrite.
Do you work with our existing engineers?
Yes. We work alongside in-house teams, follow your conventions, and write code your engineers can own after the project ends.
Who owns the code?
You do. Full IP transfer, in your repo, from day one.

Have a project in mind?Let's build something real.

We usually respond in under 24 hours with a clear next step.

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