You will get a secure Java Spring Boot REST API for your SaaS
Project details
Need a secure Spring Boot backend feature without adding another full-time engineer?
I build focused Java and Spring Boot REST API modules for SaaS products, startups, agencies, and existing applications.
I can deliver:
• REST endpoints and backend business logic
• PostgreSQL workflows and validation
• JWT authentication and RBAC
• Third-party API integrations
• Docker-ready configuration
• React-to-backend integration
• Error handling, tests, and API documentation
I built Dervale, my own multi-tenant AI gateway and SaaS control plane using Spring Boot, React, PostgreSQL, Redis, and Docker. Its backend includes authentication and RBAC, API and gateway keys, provider integrations, tenant isolation, usage controls, request logs, analytics, and billing workflows.
You receive the agreed implementation, source code, relevant tests, setup notes, and concise documentation.
Each package covers a bounded endpoint, feature, or backend module—not an unlimited application build. Work outside the agreed acceptance criteria is new scope.
Send me the backend feature or endpoint and your current stack. I’ll confirm the right package and boundaries before we begin.
I build focused Java and Spring Boot REST API modules for SaaS products, startups, agencies, and existing applications.
I can deliver:
• REST endpoints and backend business logic
• PostgreSQL workflows and validation
• JWT authentication and RBAC
• Third-party API integrations
• Docker-ready configuration
• React-to-backend integration
• Error handling, tests, and API documentation
I built Dervale, my own multi-tenant AI gateway and SaaS control plane using Spring Boot, React, PostgreSQL, Redis, and Docker. Its backend includes authentication and RBAC, API and gateway keys, provider integrations, tenant isolation, usage controls, request logs, analytics, and billing workflows.
You receive the agreed implementation, source code, relevant tests, setup notes, and concise documentation.
Each package covers a bounded endpoint, feature, or backend module—not an unlimited application build. Work outside the agreed acceptance criteria is new scope.
Send me the backend feature or endpoint and your current stack. I’ll confirm the right package and boundaries before we begin.
Programming Languages
JavaScript, JavaCoding Expertise
Performance Optimization, SecurityWhat's included
| Service Tiers |
Starter
$150
|
Standard
$400
|
Advanced
$800
|
|---|---|---|---|
| Delivery Time | 3 days | 5 days | 10 days |
Number of Revisions | 1 | 2 | 2 |
Number of Pages | 1 | 1 | 1 |
Design Customization | - | - | - |
Content Upload | - | - | - |
Responsive Design | - | - | - |
Source Code |
Optional add-ons
You can add these on the next page.
Additional Revision
+$30
Extra API Endpoint
(+ 1 Day)
+$50
Database Integration
(+ 2 Days)
+$80
Authentication and RBAC
(+ 2 Days)
+$100Frequently asked questions
About Harmanpreet
Backend & AI Engineer | Java, Spring Boot, REST APIs, SaaS
Kaithal, India - 2:26 am local time
I work best with SaaS founders, AI startups, and software agencies that need a clearly bounded backend or integration module taken from requirements to a tested, deployment-ready implementation.
WHAT I CAN OWN
• Java and Spring Boot REST APIs
• SaaS backend modules and PostgreSQL data workflows
• Authentication, JWT, RBAC, API keys, and access controls
• OpenAI, Gemini, and Groq integrations
• LLM-backed endpoints, structured outputs, and streaming
• Third-party API integrations
• Redis caching, rate limits, and usage controls
• Docker configuration and deployment support
• Backend testing, debugging, and reliability work
• React-to-backend integration
PROOF
I built Dervale, my own multi-tenant AI gateway and SaaS control plane. It uses Spring Boot, React, PostgreSQL, Redis, and Docker, with multi-provider routing, authentication and RBAC, gateway keys, usage governance, rate and budget controls, request and audit logs, analytics, and AI integrations.
HOW I WORK
I define the API contract and implementation boundaries first, then deliver maintainable code with validation, error handling, relevant tests, configuration notes, and concise documentation. I communicate risks early and keep milestones tied to observable functionality.
Send me the backend feature, API, integration, or bug you need handled and your current stack. I’ll tell you the cleanest implementation path and whether it fits a fixed-scope project.
Steps for completing your project
After purchasing the project, send requirements so Harmanpreet can start the project.
Delivery time starts when Harmanpreet receives requirements from you.
Harmanpreet works on your project following the steps below.
Revisions may occur after the delivery date.
Scope Review
I review the feature requirement, stack, repository context, acceptance criteria, and package boundaries.
Technical Plan
I confirm API contracts, data changes, dependencies, assumptions, and implementation risks.