AAt SQUAD Technology Solutions, an IT outsourcing company, we are building a small, agile team with a strong commitment to doing things right from the very beginning.

We are currently working with one of our clients to hire a

Java Senior Developer with reactive programming

for a project in the

banking sector

.
What are we looking for?

8+ years of Java development experience

, including

Java 17/21

, modern language features, concurrency, and high-performance backend systems.
Strong expertise with

Spring Boot, Project Reactor, RxJava, and CompletableFuture

to build scalable and reactive microservices.
Hands-on experience with

gRPC & Protobuf

, including streaming RPCs, interceptors, deadlines, and API/schema evolution.
Solid background in

Kafka, Redis, PostgreSQL, and MongoDB

,



delivering event-driven and data-intensive applications.
Strong cloud experience on

AWS

(S3, IAM, Managed Kafka, container runtimes) and modern distributed architectures.
Expertise in

Docker

, multi-architecture container images (amd64/arm64), CI/CD, and cloud-native deployment practices.
Experience leading

large-scale refactoring or migration projects

in multi-module codebases, with strong communication skills and

C1 English

; Python knowledge is a plus.
What are we offering?

Freelance contract with immediate onboarding.
Stable and full time project

with an international client.

📌 Senior Java Developer (Madrid)
🏢 SQUAD Technology Solutions
📍 Madrid