• Skip to primary navigation
  • Skip to main content
  • Skip to footer

Side Hustles

Side Hustles

Side Hustles For All

  • Best Side Hustles
    • Woman sitting on a pile of coins and working on a laptop surrounded by icons representing different side hustle ideas

      31 Best Side Hustles to Earn Extra Money in 2026

    • Bicycle courier delivering food for their side hustle.

      What Is a Side Hustle?

    • Remote worker sitting at his desk making money from home

      18 Ways to Make Money from Home (Online and Offline Jobs)

    • By Category
      • Arts & Crafts
      • Business Services
      • Caregiving
      • Creative Services
      • Digital Freelance Services
      • View All
    • By Lifestyle
      • I’m introverted
      • I’m a man
      • I’m a woman
      • I’m a stay-at-home mom
      • I’m unique
      • View All
    • By Profession
      • Artists & Creatives
      • Musicians
      • Nurses
      • Physicians
      • Teachers
      • View All
    • By Age Group
      • College Students
      • Teens
      • Age 50+
      • Seniors
      • View All
    • By Skills & Interests
      • Get Paid to Lose Weight
      • Get Paid to Play Games
      • Get Paid to Read
      • Get Paid to Sleep
      • Get Paid to Travel
      • View All
  • Best Gig Apps
    • Freelance worker popping out of a phone screen and considering gig apps on the App Store and Google Play

      Top 6 Gig Apps to Make Real Cash in 2026

    • Smartphone surrounded by the icons of different money-making apps

      Top 10 Best Money-Making Apps to Try in 2026

    • two teenagers using job apps on a phone and laptop

      19 Job Apps for Teens to Find Jobs and Make Money

    • By Gig Type
      • Cashback
      • Data Entry
      • Delivery
      • Games
      • Product Testing
      • View All
    • By Payment Method
      • Bingo Games that Pay to Cash App
      • Games that Pay Real Money
      • Games that Pay to Cash App
      • Games that Pay via PayPal
      • Surveys that Pay to Cash App
      • View All
    • By Benefits
      • $20 Signup Bonuses
      • $25 Signup Bonuses
      • $50 Signup Bonuses
      • Best Signup Bonuses
      • Instant Signup Bonuses
      • View All
    • By Skills & Interests
      • Driving
      • Losing Weight
      • Playing Games
      • Product Testing
      • Watching Ads
      • View All
  • Job Hunting
    • Freelance worker browsing a job post on a freelance job board.

      23 Job Boards You Can Use to Find Remote Work

    • Freelance writer sitting at her laptop working on a project

      15 Best Remote Jobs That Require No Paid Work Experience

    • Teenager sitting at laptop working an online job

      14 Online Jobs for Teens (With No Experience)

    • Freelancing
      • Freelance Writing Sites
      • Freelance Writing Job Boards
      • Freelance Writing Platforms
      • View More
    • Gig & Shift Work
      • Gig Work Apps
      • On-Demand Work Apps
      • Shift Work Apps
      • View More
    • GPT (Get Paid To)
      • Microtasking
      • Product Testing
      • Survey Taking
      • View More
    • Remote Working
      • Best Remote Job Boards
      • Top 15 Remote Jobs
      • View More
  • Job Board
    • Work Schedule
      • Part-Time Jobs
      • Per-Diem Jobs
      • Go Search
    • Work Environment
      • Hybrid Jobs
      • Remote Jobs
      • Go Search
    • Employment Type
      • Contractor Jobs
      • Internship Jobs
      • Temporary Jobs
      • Go Search
    • Job Title
      • Accounting Jobs
      • Data Entry Jobs
      • Nursing Jobs
      • Online Teaching Jobs
      • Software Engineer Jobs
      • Go Search
    • State
      • California Jobs
      • Florida Jobs
      • New York Jobs
      • Pennsylvania Jobs
      • Texas Jobs
      • Go Search
    • City
      • Chicago, IL
      • Houston, TX
      • Los Angeles, CA
      • New York City, NY
      • Phoenix, AZ
      • Go Search

Home Flexible Job Board Sr. Software Engineer – Backend / API Engineering

$110–120/hr 12d ago

Sr. Software Engineer – Backend / API Engineering

Boost your chances before you apply.

  • ✨ Apply 10x Faster Free

    It takes 30+ tailored applications to land jobs like this one. We'll help you get that done in 1 hour.

    No Credit Card Required

  • Proceed to Application Go directly to the company's job page to apply.
Logo

Ontrac Solutions

Chicago, IL, US

Contractor Remote

✨ Apply 10x Faster

Analyze your resume for missing keywords, then one-click optimize it. Don't be anything less than a 100% match candidate.

Free

No Credit Card Required

Summary

The engineer will design and implement core domain microservices on Google Cloud, including licensing, case management, and payment processing. They will also own the platform's API surface, ensuring stable contracts for mobile, frontend, and integration teams.

Job Description

OVERVIEW

We are seeking a highly skilled and experienced Senior Software Engineer (Backend / API) to join a contractor program supporting a critical customer engagement: a state government professional licensing and regulatory compliance platform built on Google Cloud. This is greenfield work — infrastructure, data and CI/CD are in place, and the application services are still to be built. This role is ideal for a senior backend engineer with deep Java and Spring Boot experience who owns core domain services end to end and designs the APIs the rest of the platform is built on. The successful candidate will build the licensing, case management, payments, document and notification services and the public and internal API surface, working closely with the client technical lead, the integration engineers, and the mobile and frontend engineers to ensure project success from initial definition through final delivery.

Expected start date: 5 October 2026.

REQUIRED CREDENTIALS

• 8+ years of professional backend engineering experience with Java and Spring Boot

• Production delivery experience on Google Cloud Platform

• Bachelor's degree in Computer Science or equivalent practical experience

REQUIRED QUALIFICATIONS

• Java 21 and Spring Boot 3.x microservice development

• API design and ownership: REST, OpenAPI specification, versioning, pagination, error contracts, backward compatibility

• PostgreSQL, including schema design, indexing, query tuning, and versioned migrations

• GCP serverless services: Cloud Run, Pub/Sub, Cloud Tasks, Cloud Scheduler

• Event-driven architecture and messaging patterns (idempotency, retries, dead-letter handling)

• API security with OAuth 2.0 / OIDC and JWT, including role- and attribute-based authorization

• Automated testing (JUnit, integration tests) and CI/CD

• Observability of owned services: structured logging, metrics, tracing, SLOs

USEFUL QUALIFICATIONS

• Experience in government or regulated environments (FIPS, CJIS, HIPAA) — a plus, not a requirement

• Building APIs consumed by external partners, agencies, or public-facing applications

• AlloyDB, BigQuery

• Payment processing integrations and settlement reconciliation

• GraphQL or gRPC alongside REST

• Performance and load testing of high-traffic public services

• Google Cloud Professional certifications

SCOPE AND SOLUTION EXPECTATIONS

Below covers the scope of work we anticipate the contractor supporting throughout the project timeline.

• Design and implement Java 21 / Spring Boot microservices on Cloud Run for the core domain: licensing, applications and renewals, case management, payments, documents, and notifications

• Own the platform API surface — specify it in OpenAPI, keep contracts stable for the mobile, frontend and integration teams, and version changes without breaking consumers

• Implement PostgreSQL (AlloyDB) persistence, including row-level data isolation, search indexing, and migration strategy

• Build asynchronous event flows on Pub/Sub and Eventarc, and publish the domain events other services and the integration layer subscribe to

• Implement scheduled and timer-driven processing with Cloud Tasks and Cloud Scheduler (renewal reminders, expiration sweeps, reconciliation)

• Implement authentication and authorization across the API surface, including public applicant access and internal staff roles

• Implement payment flows, including hosted payment page integration and settlement reconciliation

• Meet platform security and compliance requirements for encryption, auditability, and data isolation

• Deliver unit and integration test coverage, participate in code reviews, and support CI/CD deployment of owned services

About the company

Ontrac Solutions

Ontrac Solutions helps organizations adopt emerging technologies to scale smarter.
We build GenAI platforms, predictive analytics solutions, and drive cloud adoption.
We're also a HubSpot partner, supporting landing page design, website development, CRM integration, workflows, and automation.

From infrastructure to marketing ops, we deliver strategy and execution that drives growth.

Founded

2010

Company size

11-50 employees

Industry

IT Services and IT Consulting

Org type

Privately Held

Headquarters

Chicago, IL

Apply Now

About the company

Ontrac Solutions

Ontrac Solutions helps organizations adopt emerging technologies to scale smarter.
We build GenAI platforms, predictive analytics solutions, and drive cloud adoption.
We're also a HubSpot partner, supporting landing page design, website development, CRM integration, workflows, and automation.

From infrastructure to marketing ops, we deliver strategy and execution that drives growth.

Founded

2010

Company size

11-50 employees

Industry

IT Services and IT Consulting

Org type

Privately Held

Headquarters

Chicago, IL

Footer

sidehustles.com
Facebook Twitter Instagram LinkedIn Reddit TikTok YouTube

Show Me The Money

  • Side Hustle Basics
  • Side Hustle Job Board (Remote & Part-Time Jobs)
  • Gig App Reviews
  • Job Hunting
  • Manage Your Money
  • The Gig Apple: News & Events

Company

  • About Us
  • Contact Us
  • Become a Contributor
  • Advertising & Sponsorships
  • Partner With Us
  • Editorial Guidelines

Side Hustles © All rights reserved

  • Privacy Policy
  • Terms of Service

Thanks for using our free job board

Your review would mean a lot to us.

If you love that we're just giving away remote jobs for free with no paywall, please spread the word. (You will need to create an account on Trustpilot, for which we'll be eternally grateful.) Good luck out there!

Leave a Review Not yet. Send me to the job post.