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Redian Software
Web Development expertise

Java / Spring — for the long-lived enterprise systems

Spring Boot, Spring Cloud, Hibernate and Kafka builds for banks, insurers and enterprises — core BFSI systems engineered to run reliably for a decade.

CMMI Level 3 Appraised ISO Certified 200+ enterprises 5 regional hubs 9+ years of delivery
Java / Spring delivery, in numbers

Proof, not promises.

Real benchmarks from production engagements.

  • Spring Boot

    Default framework

    Plus Spring Cloud for distributed

  • BFSI

    Where we deploy most

    Banking, insurance, lending

  • Decade+

    Java app lifespan

    Built for the long run

  • JDK 21+

    Modern Java

    Records, virtual threads, pattern matching

What we deliver

The capabilities our Java / Spring engineers ship.

Production patterns from real engagements — not a stack-marketing checklist.

  • 01

    Spring Boot microservices

    Production microservices with proper layering, DTO mapping, validation, OpenAPI documentation, integration testing.

  • 02

    Spring Cloud distributed

    Service discovery (Eureka/Consul), config (Spring Cloud Config), circuit breakers (Resilience4j), gateway (Spring Cloud Gateway).

  • 03

    Hibernate / JPA at scale

    Proper entity design, second-level cache, query tuning, batch operations, connection pool sizing.

  • 04

    Kafka event-driven

    Spring Kafka, schema registry (Avro/Protobuf), exactly-once semantics, idempotent consumers, dead-letter queues.

  • 05

    Enterprise security

    Spring Security with OAuth 2.0 / OIDC, JWT, RBAC, fine-grained authorisation, audit logging.

  • 06

    Modern JVM tooling

    JDK 21+ with virtual threads, records, pattern matching, sealed types. We don't write Java 8 in 2026.

Who hires us for Java / Spring

Where this stack fits best.

We've seen the patterns — match yours against the list to find the closest fit to your situation.

  • Banks & lenders

    Core banking, lending platforms, payment systems — where Java's BFSI ecosystem dominates.

  • Insurers & brokers

    Policy administration, claims, broker platforms — long-lived enterprise systems.

  • Large enterprise IT

    Enterprise IT environments standardised on Java. Internal apps, integration services, microservice estates.

  • Government & public sector

    Public-sector applications with strict procurement preferring Java's enterprise ecosystem.

  • Data-heavy backends

    Backends using Kafka, Spark, Cassandra, Flink — JVM-native ecosystems.

  • Modernisations

    Legacy J2EE / Spring 3 / Java 8 environments modernising to Spring Boot 3 / JDK 21.

How we engage

From brief to production.

Transparent, milestone-driven, with clear owners and timeframes at every stage.

  1. 01

    Architecture

    Microservice decomposition, data model, integration map, observability strategy, deployment plan.

  2. 02

    Build

    Two-week iteration cycles, working software each sprint, OpenAPI specs from day 1.

  3. 03

    Hardening

    Performance, security, integration testing, observability, chaos engineering.

  4. 04

    Production

    Containerised deployment to Kubernetes, hypercare with named senior engineers on call.

Java / Spring in depth

Inside our Java / Spring practice.

The long-form view of how we approach Java / Spring engagements.

Java has been the default choice for systems that need to keep running for a decade — core banking, policy administration, claims, treasury, payments, order management, regulatory reporting. It compiles to something predictable, the JVM tuning story is well understood, and the ecosystem around Spring, Hibernate, Kafka and the Jakarta EE stack is deep enough that new engineers can be productive without a long onboarding curve. Our Java practice is built around that longevity: we write services other teams will inherit, extend and audit years after we hand them over.

What we build in Java

Most of our Java work is transactional systems where correctness, throughput and traceability all matter at the same time. That includes core ledgers and posting engines for our core banking clients, policy and claims services in the insurance practice, settlement and reconciliation pipelines, KYC/AML orchestration, and integration layers that sit between third-party channels — mobile banking apps, agent networks, aggregators, regulators — and the systems of record behind them.

We also build the less glamorous but equally important pieces: batch jobs that close the day, reporting extracts for RBI, IRDAI, CBK, IRA, NAICOM and central bank returns, file-based interfaces with SWIFT, ACH, RTGS and card switches, and long-running workflow engines that survive restarts. When the requirement is "this must not lose a message and must reconcile at end of day," Java on a properly configured JVM is usually the right answer.

Beyond BFSI, we ship Java for logistics platforms, healthcare claim workflows, government e-services and enterprise back-office systems where the buyer expects a stack their internal team can maintain without importing a niche skill set.

The stack we standardise on

Spring Boot is the backbone for services — auto-configuration, actuator endpoints for health and metrics, profile-based configuration, and a testing story that scales from unit to full slice tests. On top of it we use Spring Data JPA with Hibernate for persistence, Spring Security with OAuth2/OIDC for authentication (integrated with Keycloak, Azure AD or the client's existing IdP), Spring Cloud Gateway or an API gateway of the customer's choice, and Spring Cloud Config or a vault-backed configuration store for secrets.

For asynchronous work and event-driven flows we use Kafka — with proper schema management via Confluent Schema Registry or Apicurio, idempotent producers, and consumers designed for at-least-once semantics with deduplication at the sink. Where the workload fits a classical queue we use RabbitMQ or IBM MQ, and for legacy shops we still integrate with JMS providers already in place. Batch is Spring Batch with chunked processing, restartable jobs and proper JobRepository configuration on the relational store.

Persistence is usually PostgreSQL, Oracle or MS SQL — chosen by the customer, not by us. For read-heavy or search workloads we add Elasticsearch or OpenSearch, and Redis for caching, distributed locks and rate limiting. Where the model is genuinely graph-shaped we bring in Neo4j; where it's document-shaped we use MongoDB. Every service ships with OpenAPI documentation generated from the code, not written by hand, and contract tests where the client-server relationship warrants them.

For newer greenfield work we increasingly use Java 21 with virtual threads, records and pattern matching. For long-lived customer estates we work with whatever LTS they are on — Java 8, 11, 17 — and we're comfortable running mixed-version estates while a migration is underway.

How we engineer

Production microservices with proper layering, DTO mapping, validation, OpenAPI documentation and integration testing — that is the baseline, not the pitch. Every service has a controller layer that only handles transport concerns, a service layer that owns the business rules, a repository or gateway layer for I/O, and explicit DTOs at the boundary so persistence models never leak into the API. Bean Validation annotations, MapStruct for mapping, and a single exception handler per service keep the code readable.

Testing is layered. JUnit 5 and Mockito for units, Spring Boot slice tests (@WebMvcTest, @DataJpaTest) for the layers we care about, Testcontainers for real Postgres/Kafka/Redis in integration tests, and WireMock for downstreams we don't control. For BFSI work we add scenario tests around double-entry invariants, idempotency keys and reconciliation windows — the tests that catch the bugs that end up in audit findings.

Observability is not optional. Every service exposes Micrometer metrics scraped by Prometheus, structured JSON logs shipped to ELK or Loki, and distributed traces via OpenTelemetry into Jaeger, Tempo or the customer's APM (Dynatrace, Datadog, AppDynamics — we work with what's already licensed). Health checks, readiness probes, graceful shutdown and proper connection pool sizing are configured before the first release, not after the first incident.

Delivery runs on containerised builds — Docker images built with Jib or buildpacks, deployed via Helm charts to Kubernetes (EKS, AKS, GKE or on-prem OpenShift/Rancher), with GitHub Actions, GitLab CI or Jenkins pipelines depending on the customer's tooling. SAST via SonarQube, dependency scanning via OWASP Dependency-Check or Snyk, and container scanning as gates in the pipeline.

Where Java sits in a wider engagement

Java rarely ships alone. On most engagements it's the durable core, with a React or Angular front end for internal users and customer portals, Node or Python services for lighter I/O-heavy work, and a CRM or ERP — usually Zoho, Odoo, Salesforce or MS Dynamics — for the customer-facing and operational workflows around it. Our Advanced Zoho Partner and Odoo Official Partner teams work alongside the Java engineers so the integration between systems is designed, not bolted on.

For clients who need to add Java capacity to an existing team rather than commission a full build, we offer named engineers through IT staff augmentation — Spring Boot developers, JVM performance engineers, architects — vetted against the same standards we apply on our own delivery.

Talk to us

If you're modernising a monolith, replacing a vendor core, or building something new where the buying committee has already decided it will be Java, we can help with the architecture, the build and the run. Share the shape of the system on /contact or look through /case-studies for representative work.

Why Redian for Java / Spring

What makes our Java / Spring practice different.

Independent reasons clients pick us over freelancers, agencies and large consultancies.

  • BFSI Java heritage

    Most of our Java work is BFSI. We know the regulatory and operational expectations that environment imposes.

  • Modern Java only

    JDK 21+, Spring Boot 3+, records, virtual threads, modern patterns. We don't ship Java 8 nostalgia.

  • Production discipline

    Observability (Micrometer + OpenTelemetry), tracing (Jaeger/Zipkin), structured logs, real testing.

  • Polyglot honesty

    Where Java is overkill, we suggest Python or Node.js. Where it's the right fit, we ship Java.

Tech & tools

The Java / Spring stack we ship on.

Production tooling — not just languages on a CV.

  • JDK 21+
  • Spring Boot 3+
  • Spring Cloud
  • Spring Security
  • Spring Kafka
  • Spring Data
  • Hibernate
  • JPA
  • Quarkus
  • Micronaut
  • Maven
  • Gradle
  • JUnit 5
  • Mockito
  • Testcontainers
  • Kafka
  • Avro / Protobuf
  • PostgreSQL
  • Oracle
  • Cassandra
  • Redis
  • Elasticsearch
  • Micrometer
  • OpenTelemetry
  • Jaeger
  • Resilience4j
  • Docker
  • Kubernetes
  • AWS
  • Azure
Proof from production

A Java / Spring project we can share publicly.

Most of our work is under NDA — this is one we can share.

BankingAfrica

Core Banking + Digital Channels for a Cameroon-based Bank

Client · Confidential — Cameroon

  • 250,000+

    Active customers

  • −60%

    Cost-to-serve

Full core banking modernisation plus mobile, internet and agency banking for a Cameroon-based bank — live in 9 months, now serving 250,000+ customers.

Tech stack

JavaSpring BootPostgreSQLKafkaReactKotlinSwiftAWS
Frequently asked questions

Everything you wanted to ask before the call.

Don't see your question? Ask us directly →

Why pick Java over Node.js or Python?

Java for long-lived enterprise systems, BFSI environments, JVM-heavy ecosystems (Kafka, Spark, Cassandra), regulator-supervised applications, or teams already invested in JVM tooling. Node.js for I/O-heavy real-time. Python for AI/ML and data engineering.

Spring Boot vs Quarkus vs Micronaut?

Spring Boot for the broadest ecosystem support and most engineer-friendly DX. Quarkus when native-image and faster cold-start matter (serverless, scale-to-zero). Micronaut as an alternative to Quarkus with cleaner DX. We default to Spring Boot.

Do you do reactive Spring (WebFlux)?

Yes — for genuinely reactive use-cases (real-time data, streaming, very-high-concurrency APIs). For typical CRUD APIs we recommend imperative Spring Boot + virtual threads (JDK 21+) — same scalability without the cognitive overhead.

Can you modernise our legacy Java app?

Yes — J2EE → Spring Boot, Java 8 → JDK 21, monolith → microservices. Strangler-fig pattern, incremental delivery, parallel running until cutover. We've modernised systems running for 15+ years.

Engage Redian

Ready to ship with Java / Spring?

Tell us the role, the seniority and the time-zone overlap you need — a senior engineer will send three pre-vetted profiles within a week.