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JEXCELLENCENO. 026Q3 / 2026OLDENBURG · DE
AVAILABLE
— SOFTWARE ENGINEER

Softwareis craft.

Bespoke software instead of off-the-shelf solutions. Java and Spring on the backend, React, Vue, or Angular on the frontend. Test automation, plus active contributions to open-source frameworks.

7+Years20+Projects06SkillsDEOldenburg
Justin.Ev26.0Build 2026Oldenburg, DEStatus: Available Q3

Software is craft. I take that literally.

Justin Eiletz
Justin EiletzFull-Stack Software Engineer
  • BackendJava / Spring / Hibernate
  • FrontendReact / Vue / Angular
  • PracticeTest automation · ISTQB
// ch. 01 — background

My name is Justin Eiletz. I combine precise software engineering with the speed and accountability of a small, owner-operated team. I have been building software since 2017 — from Minecraft plugins to enterprise back ends serving tens of thousands of active users.

// ch. 02 — standard

Originally from North Rhine-Westphalia, I now live and work in Oldenburg. My path runs through two state-recognised IT diplomas, the co-founding of AlphaOmega-IT GbR, a specialisation in test automation at ab-data AG, and certification as an ISTQB Certified Tester.

// ch. 03 — promise

My standard: code that remains readable years later, architectures that scale with load rather than fight it, and performance that does not need explaining because it is measurable.

Specifications
  • 01
    Years
    0+

    Shipping since 2017 — from Minecraft plugins to enterprise back ends.

  • 02
    Projects
    0+

    From contained plugin engagements to multi-month replatformings.

  • 03
    Commits
    0+

    Atomic, clearly described — the commit history is part of the documentation.

  • 04
    Standard working mode
    Remote · DACH

    Fully remote for clients across Germany, Austria, and Switzerland.

  • 05
    Available in person
    On-site · Oldenburg

    Kick-off meetings and workshops can be held on-site in the Oldenburg area on request.

  • 06
    Business fluent
    DE · EN

    German (native) and English (business fluent) — in meetings, code comments, and documentation.

Crafted with care from Lower Saxony.

Does this match your situation?

Four typical starting points, each with a dedicated detail page. Pick your profile — the right language, the right approach, and a concrete fixed-price offer follow immediately.

In focus

Cosmetics & Beauty

Studios and brands

You run a studio or your own brand and need an online presence with integrated booking — mobile, individual, no templates.

Entry-level offer

Beauty Starter · Landing page with booking integration · €1,490 instead of €3,490

2 weeks
Time to go-live
2+
Beauty brands live
Open detail pageDetail page with approach, examples and FAQ
Telemetry · Live06Systems online

Depth over breadth — with enough breadth to deliver.

Six core competencies built up over seven years of practice.

  • SYS.JAVA-01Elite

    Java Ecosystem

    0%Load
    Trajectory
    online for7 years
    Stack
    • Spring Boot
    • Hibernate
    • JPA
    • Maven/Gradle

    Spring Boot, Hibernate, JPA. Enterprise back-ends with clean layering and solid test coverage.

  • SYS.FRONT-02Proven

    Frontend Frameworks

    0%Load
    Trajectory
    online for5 years
    Stack
    • React
    • Vue
    • Angular
    • TypeScript

    React, Vue, Angular. Type-safe with TypeScript, modular components, sane state management.

  • SYS.QA-03Proven

    Quality Assurance

    0%Load
    Trajectory
    online for3 years
    Stack
    • Selenium
    • Playwright
    • Ranorex
    • JUnit
    • aqua cloud
    • ISTQB

    Test automation from unit to E2E. Selenium, Ranorex, Playwright, aqua cloud — ISTQB certified.

  • SYS.OPS-04Active

    DevOps & Tooling

    0%Load
    Trajectory
    online for4 years
    Stack
    • Docker
    • Git
    • GitHub Actions
    • Linux

    Containers, CI/CD, reproducible builds. Pragmatic pipelines without unnecessary complexity.

  • SYS.DATA-05Proven

    Databases

    0%Load
    Trajectory
    online for7 years
    Stack
    • MySQL
    • MariaDB
    • PostgreSQL
    • Oracle
    • MongoDB
    • Redis

    MySQL, MariaDB, PostgreSQL, Oracle, MongoDB. Schemas that scale with growth without becoming a bottleneck in operations.

  • SYS.CRAFT-06Elite

    Engineering Craft

    0%Load
    Trajectory
    online for7 years
    Stack
    • Code Reviews
    • Mentoring
    • Architecture
    • Refactoring

    Code reviews, pair programming, mentoring. Software development is teamwork — including in solo engagements.

  • All systems nominal · Last sync moments ago
    DOSSIER · 08 ENTRIESCLASS · CONFIDENTIAL

    What I've built

    A curated selection of my work — enterprise, open source, and everything in between. Projects under NDA available on request.

    1. Featured · Own product2023 – present

      RaindropCentral

      Full-Stack · Enterprise · E-commerce

      An enterprise platform — independently designed, developed, and operated. Java 21, Spring Boot 4, and Hibernate 6 in the backend with a Flyway-versioned PostgreSQL database, complemented by a Next.js 16 / React 19 frontend with Stripe checkout, live updates over WebSocket, an integrated shop, and Discord integration. Built as a personal reference project — now publicly available.

      Role
      Architect · Solo developer · Operations
      Stack
      • Java 21
      • Spring Boot 4
      • Hibernate 6
      • Next.js 16
      • React 19
      • PostgreSQL
      • Stripe
      • Docker
      • WebSocket
      Visitraindropcentral.com
    2. Live · Multiple brands2023 – present

      La Femme Kosmetik & Beauty Suite

      Landing Pages · Beauty

      Bespoke landing pages for cosmetics brands — each one custom-built, never templated. La Femme Kosmetik opens the series: modern UI, integrated booking flow, consistently mobile-first. More beauty brands are shipped from the same studio.

      Role
      Designer · Front-end developer
      Stack
      • Next.js
      • TypeScript
      • SCSS
      • SEO
      • Booking flow
      Visitlafemmekosmetik.de
    3. Co-founder2022 – 2024

      AlphaOmega-IT GbR

      Agency · Web & Gaming infrastructure

      Co-founded and technically led an agency focused on bespoke web projects and professional Minecraft server operations. Spring back ends, React and Vue front ends, plus hosting and operations for community servers with tens of thousands of monthly active players.

      Role
      Co-founder · Tech lead
      Stack
      • React
      • Vue.js
      • Spring
      • Hibernate
      • Docker
      • Server ops
    4. Employed2023 – present

      abd-quality @ ab-data

      Test Automation · Enterprise

      Building and operating ab-data's in-house test automation toolkit, abd-quality. End-to-end suites with Selenium, Ranorex, Playwright, and aqua cloud. Regression cycles reduced from days to hours; flaky tests systematically stabilised.

      Role
      Quality engineer · ISTQB
      Stack
      • Selenium
      • Playwright
      • Ranorex
      • aqua cloud
      • Java
      • ISTQB
    5. Open source · Active2025 – present

      Once UI · Open-source contributions

      UI/UX framework · Community

      Active contribution to the Once UI framework — the design system this site itself is built on. Component pull requests, bug fixes, and contributions to discussions on API design and theming architecture.

      Role
      Contributor
      Stack
      • React
      • TypeScript
      • SCSS
      • Open source
      Visitonce-ui.com
    6. Since 2017 · Active2017 – present

      Minecraft Plugin Suite

      Backend · Gaming

      More than 30 production plugins serving tens of thousands of users. Hibernate-backed persistence, custom game mechanics, performance tuning for peak loads. This is where I learned Java, Hibernate, and architecture in practice — and the environment continues to serve as a testbed for new ideas.

      Role
      Plugin architect
      Stack
      • Java
      • Paper / Bukkit
      • Hibernate
      • MySQL
      • Async I/O
    7. Built multiple timesVarious

      Software Licensing Server

      Backend · SaaS

      Bespoke licensing servers with key rotation, hardware binding, an admin dashboard, and API integration. Delivered multiple times for different clients — each iteration building cleanly on the lessons of the previous one.

      Role
      Designer · Backend developer
      Stack
      • Spring
      • PostgreSQL
      • REST
      • Vue
      • JWT
    8. Own tool2024 – present

      Enhanced Website Builder

      SaaS · Builder

      A drag-and-drop website builder with a component library, live preview, built-in SEO controls, and theme management. Originally conceived as an internal tool — in practice, it underpins projects where clients explicitly want to avoid templates.

      Role
      Architect · Full development
      Stack
      • React
      • TypeScript
      • Node.js
      • PostgreSQL
      • DnD
      • SEO
    END OF DOSSIER · Request full portfolio
    Pipeline · End-to-end0404 phases

    How we work together

    Four phases, one continuous pipeline. Clear expectations, weekly demos, no surprises.

    1. Phase · 01 / 041–2 weeks

      Discovery

      Listen. Ask. Understand.

      A complimentary first call, followed by a paid discovery phase: requirements, risks, and technical feasibility. The focus is on listening, not selling.

      What happens
      • Stakeholder interviews & requirements analysis
      • Risk and feasibility assessment
      • Technical architecture sketch
      • Fixed-price corridor and roadmap
      DeliveryDetailed proposal with sharply scoped corridor
    2. Phase · 02 / 042–4 weeks

      Architecture & Design

      Decide. Sketch. Document.

      Technical architecture, API contracts, and UI sketches. Every load-bearing decision is captured in an Architecture Decision Record (ADR), making it traceable months and years later.

      What happens
      • System architecture and data model
      • API contracts with OpenAPI
      • UI wireframes and design tokens
      • Architecture Decision Records (ADRs)
      DeliveryArchitecture pack: diagrams, ADRs, mockups
    3. Phase · 03 / 04project-dependent

      Iteration

      Build. Demo. Adjust.

      Working software from the first sprint, paired with weekly demos. You see continuous progress — not just an outcome after months.

      What happens
      • Incremental delivery in week-long sprints
      • Weekly demos and backlog refinement
      • Code reviews and test-coverage discipline
      • Live staging with feature flags
      DeliveryWorking software in a test environment — every week
    4. Phase · 04 / 041–2 weeks

      Launch & Handover

      Ship. Observe. Hand off.

      Production deployment, monitoring, full documentation, and a structured handover to your team on request. Includes a 30-day bug-fix guarantee after go-live.

      What happens
      • Production deployment with rollback plan
      • Monitoring, logging, and alerting
      • Knowledge transfer and documentation
      • 30-day bug-fix guarantee post-launch
      DeliveryLive system + runbook + handover sessions
    Live in production
    Service Catalog · 04 areasAll prices include 19% VAT

    Transparently priced.

    Four service areas with clear pricing. All amounts in euro, including 19% German VAT. Custom scope on request.

    Different scope? A fixed price is set after the discovery phase — let's discuss your project.Discuss project