Spring Boot REST services
New endpoints or whole services in Spring Boot, with validation, clear error responses, and OpenAPI docs.
The Problem
Java Code That Runs the Business and Scares Everyone Who Touches It
Java systems tend to live for a decade. The original team moves on, the Spring Boot version falls behind, and every release becomes a weekend nobody wants to work.
01 · Old versions
The app still runs on Spring Boot 2 and Java 8.
We upgrade step by step to a supported Spring Boot line and Java LTS.
02 · Manual SQL
Database changes are scripts someone runs by hand on release night.
Flyway migrations apply every schema change in order, the same way everywhere.
03 · Mocked tests
Tests mock the database, so real query bugs reach production.
Integration tests run against a real PostgreSQL started by Testcontainers.
04 · No visibility
Slowdowns show up first as customer complaints.
Actuator health checks and metrics feed alerts before customers notice.
Your claims system runs on Spring Boot 2 and Java 8, and nobody has upgraded it because nobody is sure what would break. Database changes are SQL scripts someone runs by hand on release night. The tests mock the database, so they pass while production fails on a real query. When the app slows down, the first sign is a customer complaint, because nothing reports its health. Every new feature waits for the one developer who still understands the build.
We start by putting guardrails around the code you already have. Schema changes move into Flyway migrations, integration tests run against a real PostgreSQL started by Testcontainers, and Spring Boot Actuator reports health and metrics to your alerts. Then we upgrade one step at a time and build new features on that base. Releases become routine weekday work, not a weekend of crossed fingers.
Versioned schema changes
Flyway migrations live in the repository, so every environment gets the same database changes in order.
Tests against real databases
Testcontainers starts a real PostgreSQL for integration tests, so query bugs surface before release.
Health you can see
Spring Boot Actuator exposes health and metrics, wired to alerts your team actually reads.
Our Java Development Process
From Code Review to Routine Releases in Five Steps
Five steps take your Java work from an unknown codebase to releases your team can repeat. You approve the plan, review each sprint on staging, and own the repository throughout.
You walk us through the system, what it does for the business, and what worries you about changing it. We ask about versions, hosting, and release habits. You get a short plan and a fixed-price proposal.
What's Included
What You Get With Custom Java Development
Java work from the database up: Spring Boot services and APIs, versioned schema changes, real integration tests, health monitoring, and upgrades that keep your code on supported versions.
Compare Options
DeveloperLook vs a Freelance Java Developer vs an In-House Hire
A freelancer costs less for a small, well-defined task, and an in-house hire suits years of steady Java work. A Java development company fits when you need a team now and guardrails that outlast it.
| Feature | DeveloperLookBest fit | Freelancer | In-house hire |
|---|---|---|---|
| Start date | Within 1 to 2 weeks | Often within days | Months to recruit and onboard |
| Planning | Written plan and fixed price | Usually hourly, light planning | Your own process |
| Spring Boot upgrades | Planned, one step at a time | Depends on the person | Competes with feature work |
| Database changes | Flyway migrations, reviewed | Often hand-run scripts | Depends on team habits |
| Testing | Testcontainers and JUnit 5 | Varies by developer | Depends on team habits |
| Cover for absence | Backup developers on the team | Work stops while they're away | Needs a second hire |
| Cost | Fixed price per scope | Lowest for small tasks | Salary, benefits, and tools |
| Code ownership | Your repository from day one | Yours if agreed in writing | Yours |
DeveloperLook
Freelancer
- Start date
- DeveloperLook: Within 1 to 2 weeksFreelancer: Often within days
- Planning
- DeveloperLook: Written plan and fixed priceFreelancer: Usually hourly, light planning
- Spring Boot upgrades
- DeveloperLook: Planned, one step at a timeFreelancer: Depends on the person
- Database changes
- DeveloperLook: Flyway migrations, reviewedFreelancer: Often hand-run scripts
- Testing
- DeveloperLook: Testcontainers and JUnit 5Freelancer: Varies by developer
- Cover for absence
- DeveloperLook: Backup developers on the teamFreelancer: Work stops while they're away
- Cost
- DeveloperLook: Fixed price per scopeFreelancer: Lowest for small tasks
- Code ownership
- DeveloperLook: Your repository from day oneFreelancer: Yours if agreed in writing
Projects We've Built
Business Apps and Platforms We Have Built
Insurance, finance, and HR apps from our portfolio, chosen for the business rules behind them, not shown as examples of one language.
Dualcare Insurance App Design & Development
- Insurance
- Dashboard
- Mobile App
Moneywish Finance App Design & Development
- Finance
- Dashboard
- Mobile App
Login HR Staffing App Design & Development
- HR & Staffing
- Portal
- Dashboard
HR Attendee Attendance App Design & Development
- HR & Staffing
- Dashboard
- Mobile App
What Our Clients Say
What Clients Say After Launch
Feedback from teams we have built business software and APIs for.
We had a pretty specific idea of what we wanted our website to become, but I wasn’t sure how easily we could explain all of it to a development team. There were quite a few moving parts, and we were working toward a deadline, so I expected a few things to get lost along the way. That never really happened. They understood what we were trying to achieve, kept us updated throughout the process, and got everything ready within the agreed timeline. The final site feels much easier to navigate, works beautifully on mobile, and is noticeably smoother for our customers. It was a huge relief seeing the original idea actually turn into the website we had in mind.
The mobile experience is probably my favourite part of the new site. We had spent a lot of time making sure the desktop version looked right, and the team kept pushing us to think about how everything would actually feel on a phone too. They were right. The navigation is clean, the interactions feel natural, and everything we’ve tested so far works exactly as it should. They also went through the links, forms, integrations, and other details more than once before launch, which I really appreciated. And even after going live, we could still reach out when something came up. The whole process felt friendly, organised, and surprisingly straightforward.
What I appreciate most is that the website is actually easy for us to manage now. We can update content ourselves instead of sending a developer a message every time we need to change something small. They also paid attention to the technical SEO side, which mattered to us because we didn’t want a new website to create problems for the traffic we already had. I’ve probably asked more questions than I should have since launch, but every question has been handled patiently and without any fuss. The team is easy to work with, they explain things clearly, and when we need something changed, they focus on getting it done rather than making the process complicated.
1,250+
Projects shipped
10+
Years of experience
Top 3%
Upwork Top Rated Plus
5 stars
Average review score
Want results like these?
Tell us what you are building. You get a reply within 24 hours on business days, then a written estimate.
Work Culture
Why Engineering Teams Trust Us With Their Java Code
Java systems outlive the teams that built them. These habits keep yours easy to change, easy to run, and easy to hand to the next developer.
Every change reviewed
Each pull request gets a second developer's review before it merges. You end up with code more than one person understands, which matters when someone leaves.
Schema changes in code
Database changes go through Flyway migrations in the repository, not scripts run by hand. You can see exactly what changed, when, and why.
Real dependencies in tests
Integration tests start real PostgreSQL, Kafka, or Redis containers with Testcontainers. A green build means the queries work, not just the mocks.
Upgrades on a calendar
We track the Java and Spring Boot support windows your app depends on and plan upgrades early. You hear about an end date months ahead, not after it passes.
Honest stack advice
If a smaller tool or another language fits a job better than Java, we say so in the proposal. You pay for Java only where it earns its place.
You own the repository
Code lives in your GitHub or GitLab, and builds run in your CI. Changing teams later means handing over access, not rebuilding the system.
Overview
What do Java development services include for Spring Boot apps?
DeveloperLook offers Java development services for teams running business systems on Spring Boot. We upgrade old Java and Spring Boot versions, build REST services with Spring Security, version schema changes with Flyway, and test against real databases. Prices start at $1,150, upgrades take about 2 weeks, new services 5 to 16 weeks, and you own the code.
DEVELOPERLOOK
Project facts · Java Development Services
- Service
- Java Development Services (Spring Boot APIs, upgrades, integrations, testing)
- Typical timeline
- About 2 weeks for an upgrade, 5 to 16 weeks for a new service
- Platforms
- Spring Boot on AWS, Azure, Google Cloud, or your own servers
- Built with
- Java LTS, Spring Boot, Flyway, Testcontainers, and PostgreSQL
- Experience
- 10+ years of development experience and 1,250+ shipped projects
- Post-launch support
- 30 days, or 60 days on the Java Platform Build plan
- Communication
- Calls in US, UK, and AU business hours
- Starting price
- From $1,150 USD, fixed scope after discovery
Reviewed 10 Oct 2026 by Saimul Islam
Good fit
Teams stuck on Spring Boot 2
Your app still runs on Spring Boot 2 and Java 8, and every upgrade estimate you've seen reads like a full rewrite.
Companies short on Java engineers
You need two Java developers for this year's roadmap, and recruiting full-time hires would take longer than the work itself.
Owners of an orphaned Java app
You need a Java application development company that can take over an app the original vendor no longer supports or understands.
Product teams planning a new service
You're looking for a Java Spring Boot development company to build a new service your in-house team can run after handover.
Agencies with Java client work
Your agency won a project with a Java backend and needs Spring Boot engineers who work quietly under your brand.
Not a fit
Your stack is .NET
Your systems run on C# and .NET, and the work stays inside that stack. Our .NET Development Services page covers it directly.
No language chosen yet
You haven't picked a language yet and just need an API behind a web or mobile app. Our Backend Development Services page starts there.
Budget under $1,150
Your budget is under $1,150, or the job is one small script. If a scheduled script or an existing tool already covers your case, we'll tell you before we quote.
Rewrite with no Java future
You plan to replace the Java system with a different platform entirely. Our Application Modernization Services page covers that kind of move.
Not sure we're the right fit?
Book a free call or message us. We'll tell you honestly whether we're the right team.
Pricing
Transparent Starting Prices for Java Development Services
These are starting points in USD. Your final price depends on codebase size, current versions, and integrations, and you get a fixed proposal after a free discovery call.
For one small Spring Boot app stuck on an old release that needs guardrails. About 2 weeks.
$1,150one-time, USD
- Upgrade to a supported Spring Boot line and Java LTS
- javax imports moved to jakarta
- Flyway baseline for the current schema
- Testcontainers tests on core endpoints
- Actuator health checks wired to alerts
- 30 days of fixes after release
Recommended
For teams that need a new Spring Boot REST service with security, migrations, and tests. About 5 to 8 weeks.
$3,900one-time, USD
- Everything in Spring Boot Upgrade
- New REST API with Spring Security roles
- PostgreSQL schema managed by Flyway
- OpenAPI docs for every endpoint
- One integration with an outside system
- 30 days of post-launch support
For products that need several Spring Boot modules, messaging, and live dashboards. About 10 to 16 weeks.
$8,500one-time, USD
- Everything in Spring Boot Service Build
- Modular app with admin and user roles
- Kafka or RabbitMQ messaging between modules
- Up to 3 integrations
- Prometheus and Grafana dashboards
- 60 days of post-launch support
For Agencies
White-Label Java Development for Agencies and Studios
You keep the client relationship. We supply the Java engineering behind it: Spring Boot services, upgrades, and integrations, delivered under your brand with code in your client's repository and release notes your team can present.
How the partnership works
White label: your client only ever sees your brand
- Your client
- You, the agency
- DeveloperLook
Share the brief
Send codebase access, your client's goals, and the deadline you're working to.
- Client needs
- You share the details
- Details received
We review and quote
You get a risk list, a sprint plan, and a fixed price to resell.
- Scope and plan
- Proposal to resell
- Your quoteYOUR LOGO
Build and hand off
We build, test, and release under your client's accounts, then hand over the runbook.
- Done by our team
- Your brand on it
- Handed to your clientDone
Partner with DeveloperLookDelivered under your brand
Stay client-facing
Your brand stays on every release note, report, and handover document.
Predictable delivery
Fixed scope, two-week sprints, and staging builds your client can test.
Senior Java engineers
Spring Boot, Spring Security, and JPA work from experienced developers.
Flexible capacity
One upgrade sprint, a new service, or months of steady Java work.
The Right Technology for Your Project
Technology Stack
Java LTS releases with the Spring projects that fit the job, the database and messaging tools behind them, and build tools that keep releases repeatable.
Java- Spring Boot
- Spring Security
- Hibernate
PostgreSQL
MySQL- Flyway
- Apache Kafka
- RabbitMQ
- Redis
- Apache Maven
- Gradle
- JUnit 5
- Testcontainers
- GitHub Actions
AWS
Docker
Kubernetes- Prometheus
- Grafana
FAQ
Frequently Asked Questions
Straight answers on Java developer costs, hiring and outsourcing, Java for web backends, and Spring Boot.
Saimul IslamFounder & CEO, DeveloperLookStill have questions?
Send a message or book a call with the team.
Hiring Java developers through DeveloperLook starts at $1,150 for an upgrade sprint on one small Spring Boot app. A new Spring Boot service with security, migrations, and tests starts at $3,900, and multi-module platforms start at $8,500. A full-time hire also carries salary, benefits, and months of recruiting. You get a fixed quote after a free call.
Hire Java developers by watching how they change a real system, not by reading a list of frameworks. Ask how they'd handle a schema change, how they test against a database, and which Java LTS they'd target. A Java development company adds code review and backup developers, so your project doesn't stall when one person is away.
Hire a Spring Boot developer by giving them a short paid task on your own codebase. One endpoint with a migration and a test is enough. Check whether they use Flyway or Liquibase, write a real integration test, and explain their Spring Security choices. When you hire Spring Boot developers through us, that review is already part of the process.
Outsource Java development by starting with a small, fixed-scope piece of work before handing over a whole system. Give the team repository access, a staging environment, and one person who can answer business questions. Agree up front that code stays in your repository, that every change is reviewed, and who approves each release.
Yes, Java is a common choice for backend web development, especially for business systems with complex rules. Spring Boot handles REST APIs, security, database access, and scheduled jobs, while a React or Angular front end calls those APIs. Insurers, banks, and logistics firms often run core systems on Java backends for exactly that reason.
Java is used in web development mainly on the server, where it runs the APIs, business rules, and database work behind a site or app. Spring Boot is the usual framework, with Spring MVC or Spring WebFlux handling requests. Server-rendered pages are possible with Thymeleaf, but most new projects pair Java with a JavaScript front end.
Yes, Java is good for software that has to run for years. Strict typing, mature tooling, and long-term support releases keep large codebases manageable, and each Java LTS gets years of updates, so upgrades can be planned. It's heavier than Python or Go for small scripts, so we don't recommend it for quick, throwaway tools.
Yes, Spring Boot is widely used to build Java web applications, REST APIs, and the backends behind web and mobile apps. It bundles an embedded web server, so an app ships as one executable JAR. Spring Security, Spring Data JPA, and Actuator add login, database access, and health checks with little setup.
Spring Boot speeds up development by configuring the common pieces for you: starter dependencies, auto-configuration, and an embedded server. Spring Initializr generates a working project, and sensible defaults let developers write business logic instead of setup code. Spring Boot DevTools also restarts the app automatically when code changes during development.
Spring Boot suits microservices because each service runs as a small, self-contained app with its own embedded server and health checks. Actuator exposes the health and metrics that platforms like Kubernetes use to restart or route traffic. Spring Cloud adds shared configuration and gateways as systems grow, though for many teams one well-structured app beats ten small services.
Saimul IslamFounder & CEO, DeveloperLookStill have questions?
Send a message or book a call with the team.
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