TypeScript agency — type-safe from frontend to database
happycoding builds web apps and backends entirely in TypeScript: Next.js on the frontend, Node.js and NestJS on the backend, typed interfaces in between. The result: fewer integration errors, smaller teams, faster releases — and a stack with zero runtime license costs.
Since August 2025, TypeScript has been the most-used language on GitHub — ahead of Python and JavaScript. That's not a fashion, it's consolidation: frameworks, the talent pool, and AI tooling are converging on TypeScript. Any stack decision you make in 2026 is a decision for or against this ecosystem.
We don't sell ideology: CPU-intensive systems and massive parallelism remain solid JVM territory. Our domain is I/O-heavy web apps, APIs, and digital products that need to iterate fast — that's where an end-to-end type system earns its keep. Senior engineers own every architecture decision.
Typical TypeScript projects
A TypeScript stack fits when your web application changes often, connects to other systems and a small team owns it from the frontend to the database.
New product on Next.js and NestJS
Your new product needs to reach its first customers fast and then improve with every round of feedback. A small team builds each feature in TypeScript from data model to interface, without waiting on handoffs between frontend and backend.
Customer portal on top of your ERP
Your customers want to check orders, delivery status and invoices themselves, but the data sits in your ERP and Java core system. A Next.js portal brings it together in one place, while the systems behind it run as before.
Replace a legacy backend step by step
Your backend runs on a PHP or Spring Boot version whose security updates are running out. We replace it module by module with NestJS services, and your day-to-day operations keep running on the old system in the meantime.
Move your JavaScript to TypeScript
Your team avoids parts of its own JavaScript code because nobody knows what a change might break. Together with your developers we convert the codebase step by step, and from then on the compiler catches errors before your users do.
B2B shop with Next.js and Medusa
Your shop needs customer groups, its own price lists and an ERP connection, without locking you into one vendor. Medusa is an open-source commerce platform built in TypeScript, and it runs with a Next.js storefront on servers you choose.
TypeScript or Java for your next system?
Your IT is planning a new system and has to choose between Spring Boot and NestJS, with the team, operations and costs in mind. We compare both paths against your project, even if Java turns out to be the better fit.
Your project is not on the list? In a 30-minute intro call we clarify how we connect to your existing systems and what cost range is realistic.
Book an intro callTerms you should know
Definition
- TypeScript
- TypeScript is JavaScript with a static type system: errors are caught at compile time, not in production. Developed by Microsoft, it has been the most-used language on GitHub since 2025. For decision-makers, that means the same discipline that made enterprise Java successful — applied across the entire web ecosystem.
Definition
- End-to-end type safety
- End-to-end type safety means one type system validates the entire chain, from the database schema through the API to the user interface. Interface errors between frontend and backend teams — one of the most common failure sources in split Java/JavaScript teams — are ruled out by the machine instead of hunted down in testing.
Definition
- NestJS
- NestJS is the structured enterprise framework for Node.js backends — with dependency injection, modules, and guards, the same patterns familiar from Java/Spring. Around three million weekly downloads, in production at companies including Adidas, Autodesk, and Decathlon.
The market behind it: according to the Stack Overflow Developer Survey 2025, 48.8 percent of professional developers use TypeScript — Java sits at 29.6 percent. In its Octoverse report 2025, GitHub names TypeScript the platform's most-used language for the first time — and cites, of all things, AI-assisted development as the main driver: 94 percent of compile errors in AI-generated code are type errors, so a strict type system acts as an automatic safety net.
Security & compliance
Your customers trust you with sensitive data. We take that responsibility seriously.
Whether it's your data protection officer, your IT security team or a major customer's procurement: when security questions come up, you have solid answers. We build in data protection and security from day one and follow the principles of the Twelve-Factor App. That makes approvals and audits easier and gives you the technical foundation to meet requirements under GDPR, ISO 27001 or HIPAA.
Frameworks whose technical requirements we implement in our projects
- GDPR
- ISO 27001
- HIPAA
- NIS2
TypeScript or Java? The honest answer: it's a workload question
The stack decision is not a matter of faith. We advise the way we would decide for ourselves — including the cases where the JVM remains the right choice:
| Criterion | TypeScript stack (Node.js) | JVM stack (Java/Spring) |
|---|---|---|
| I/O-heavy web apps & APIs | core strength: event-loop model, low overhead | solid, but heavier to operate |
| CPU-intensive processing, massive parallelism | limited — this is where we recommend the JVM | core strength: virtual threads, mature garbage collectors |
| Runtime license costs | none — Node.js LTS is free, with roughly 30 months of support per version | Oracle JDK on a per-employee subscription, or a switch to OpenJDK builds |
| Support cycles | predictable: Node 24 LTS through April 2028 | Spring Boot: 12 months of OSS support per minor version, then extended support |
| Team & talent | one language stack for frontend and backend, growing talent pool | separate teams are the norm; the senior market is tight and expensive |
| Typical domain | digital products, portals, APIs, fast iteration | long-lived core systems with stable requirements |
I/O-heavy web apps & APIs
- TypeScript stack (Node.js)
- core strength: event-loop model, low overhead
- JVM stack (Java/Spring)
- solid, but heavier to operate
CPU-intensive processing, massive parallelism
- TypeScript stack (Node.js)
- limited — this is where we recommend the JVM
- JVM stack (Java/Spring)
- core strength: virtual threads, mature garbage collectors
Runtime license costs
- TypeScript stack (Node.js)
- none — Node.js LTS is free, with roughly 30 months of support per version
- JVM stack (Java/Spring)
- Oracle JDK on a per-employee subscription, or a switch to OpenJDK builds
Support cycles
- TypeScript stack (Node.js)
- predictable: Node 24 LTS through April 2028
- JVM stack (Java/Spring)
- Spring Boot: 12 months of OSS support per minor version, then extended support
Team & talent
- TypeScript stack (Node.js)
- one language stack for frontend and backend, growing talent pool
- JVM stack (Java/Spring)
- separate teams are the norm; the senior market is tight and expensive
Typical domain
- TypeScript stack (Node.js)
- digital products, portals, APIs, fast iteration
- JVM stack (Java/Spring)
- long-lived core systems with stable requirements
In practice, the decision is rarely "migrate everything." The realistic model for mid-sized companies is coexistence: the Java core system stays, new customer-facing products are built on the TypeScript stack and connect through cleanly defined APIs. Our guide Next.js as an integration layer for legacy systems shows how that works without big-bang risk.
For a detailed look at how the two ecosystem standards compare on architecture, support cycles, and talent pool, see our comparison NestJS vs. Spring Boot.
What you can buy from us
Three paths to type-safe software — each with clear outcomes instead of experiments.
TypeScript product development
from €8,000
for an MVP with a clearly defined scope
Your web app or custom software, built entirely in TypeScript.
Full-stack development
Next.js, React and Node.js in one language.
Typed APIs and data models
NestJS, Zod and Supabase: errors surface early.
Senior review of every line
An experienced developer vouches for every line.
AI-accelerated development
The TypeScript compiler is the guardrail.
Modernization alongside your core system
New products connect to your Java, ERP or legacy system without a big-bang switch.
Strangler pattern
New services run alongside the existing system.
API design and integration layer
REST, GraphQL or events, matched to your existing system.
Next.js frontends for Java backends
New interface, the backend stays.
Module-by-module replacement
Step by step instead of a ground-up rewrite.
TypeScript adoption & audit
Your JavaScript codebase becomes type-safe and your Node platform professionally set up.
Migration to TypeScript
In strict mode, so type checking actually holds.
Architecture and code audit
For existing Node applications, with clear findings.
npm dependency governance
Package rules and a protected software supply chain.
LTS upgrade roadmap
Node 20 has had no security updates since April 2026.
All prices exclude VAT, as of October 2026.
Packages and pricing
We name our price ranges before you have to ask. The ranges come from real projects — we deliberately do not quote flat rates without clarifying requirements first.
| Package | Scope | Price range |
|---|---|---|
| MVP in TypeScript | clearly defined scope, production-ready with senior review | €8,000–20,000 |
| Full web application | authentication, roles, more complex data logic, multiple user groups | €20,000–60,000 |
| Integration/modernization project | new TypeScript services alongside your existing system, API integration | project-dependent; fixed price after discovery |
| TypeScript/Node audit | codebase analysis, dependency governance, migration roadmap | on request |
MVP in TypeScript
- Scope
- clearly defined scope, production-ready with senior review
- Price range
- €8,000–20,000
Full web application
- Scope
- authentication, roles, more complex data logic, multiple user groups
- Price range
- €20,000–60,000
Integration/modernization project
- Scope
- new TypeScript services alongside your existing system, API integration
- Price range
- project-dependent; fixed price after discovery
TypeScript/Node audit
- Scope
- codebase analysis, dependency governance, migration roadmap
- Price range
- on request
For a new product that still has to show whether customers use it and pay for it, an MVP is the starting point: scope, pricing and process are on our MVP development page.
Who works on your project
Our senior team in Berlin, from the first draft to production. You talk directly to the people who write your code.
Meet the teamFAQ
Common questions about TypeScript in the enterprise