frontend developer

backend developer

full stack developer

fullstack developer

senior data scientist

senior backend developer python django

Bitexen

<div>
 
 
 REQUIREMENTS:
 
 
 
 
 
 <ul>
 <li>
 Ideally having a degree in Computer Science and strong Engineering background,
 </li>
 <li>
 Minimum of 5 years software development experience and exposure to the web applications &amp; architectures,
 </li>
 <li>
 Excellent knowledge of Python. Having experience at developing back-end solutions,
 </li>
 <li>
 Experienced at MVC pattern, RESTful web services, and web frameworks; e.g. Django,
 </li>
 <li>
 Good at developing Node.js based asynchronous solutions,
 </li>
 <li>
 Working knowledge on synchronous programming by means of utilizing frameworks such as, Gevent, Tornado, Asyncio, Node.js, etc.
 </li>
 <li>
 Having experience on building multi-threaded and multi-process solutions,
 </li>
 <li>
 Good at working with RDBMS&rsquo;s (PostgreSQL) and No-SQL databases (MongoDB),
 </li>
 <li>
 Having prior interest on trading (@Fiat and/or Crypto currencies) is desired but not strictly required,
 </li>
 <li>
 Working knowledge on Blockchain technology and ecosystem,
 </li>
 <li>
 Strong verbal and written communication skills.
 </li>
 </ul>
 
 
 
 
 
 
 
 
 
 
 
 JOB DESCRIPTION:
 
 
 
 
 
 <ul>
 <li>
 Develops new features and handles maintenance activities for our web-based exchange platform.
 </li>
 <li>
 Upholds a high standard of code quality via following best practices and DevOps automation. Writes clean, maintainable and testable code.
 </li>
 <li>
 Expected to turn business goals into tech solutions. Supports the entire application lifecycle (concept, design, test, release, and support).
 </li>
 <li>
 Recommends engineering solutions for both functional and non-functional requirements.
 </li>
 <li>
 Works with Agile development methodology and principles.
 </li>
 <li>
 Follows engineering approaches while developing software and apply design principles fits with the selected software architecture.
 </li>
 <li>
 Mentor others, does code reviews, and performs pair programming.
 </li>
 </ul>
 
 
</div>

Senior Backend Developer (Python/Django)

Hack The Box

<div><h3 class="jobSectionHeader">Ready to embark on the quest of joining Hack The Box?</h3>
At the end of this thrilling journey, you'll become a proud member of Hack The Box, with the ultimate mission to help redefine cybersecurity expertise. Get ready for an exciting adventure into the world of cybersecurity!<h3 class="jobSectionHeader">
&#10024;The core mission of the Senior Django Engineer:</h3>
We are on the lookout for our next backend engineer in LetsDefend team. Let&rsquo;s Defend is a cutting-edge cybersecurity training company dedicated to empowering blue-team professionals by simulating a real Security Operations Center (SOC). It has a community of over 320,000 members across 150+ countries fosters peer learning and collaboration.
Hack The Box and LetsDefend join forces to create the world&rsquo;s largest collaborative cybersecurity platform with hands-on labs, SOC simulations, and a unified upskilling experience.
This role will focus on enhancing backend performance and scalability, strengthening code quality and reliability, and leading architectural direction across teams. The software engineer will play a key role in improving system efficiency, reducing issues, and fostering alignment with frontend, mobile, and DevOps counterparts. Additionally, they will own and deliver impactful backend features that support major product goals and contribute to the platform&rsquo;s long-term growth.
 Location &amp; Work Mode:<ul>
<li>
Options: Turkiye or Greece</li>
<li>Fully Remote - If only in Greece: When hiring in Greece, we&rsquo;re open to candidates from all locations. Those based within 55 km of our Athens office will follow a hybrid work model. For candidates located beyond that radius, a fully remote arrangement is available.</li>
</ul><h3 class="jobSectionHeader"> The fellowship you&rsquo;ll be joining:
</h3>
The new joiner will be part of a lean software engineering team composed of three members: one Senior Backend Developer, one Mid-Level Frontend Developer, and one Mobile Developer. In this role, they will collaborate closely not only with their immediate teammates, but also with key stakeholders across the organization, including the Content Engineering team, Sales team, Infrastructure, and the broader Engineering team, all of whom play a critical role in supporting the product and its customers. This position will report directly to the Sr. Director of Engineering.<ul><li>&#65039; Technology tools &amp; weapons you&rsquo;ll be using:</li></ul><ul>
<li>Django Framework (Python language)</li>
<li>Docker</li>
<li>Apache Kafka</li>
<li>Redis</li>
<li>Git</li>
</ul><h3 class="jobSectionHeader"> Interesting resources you should check:</h3><ul>
<li>Take a look at LetsDefend Website</li>
<li>Hack The Box + LetsDefend: Shaping the future of community-led cyber readiness</li>
</ul><h3 class="jobSectionHeader"> The adventures that await you after becoming Senior Django Engineer:
</h3><ul><li>Optimize backend performance by improving API responsiveness, refining database queries, and enhancing caching strategies.</li>
<li>Design scalable backend architectures and influence long-term technical direction across multiple products and services.</li>
<li>Implement high-quality, maintainable code with strong test coverage and adherence to best practices.</li>
<li>Refactor legacy components into clean, modular, and future-ready services that accelerate development.</li>
<li>Collaborate closely with frontend, mobile, DevOps, and product teams to ensure smooth execution of cross-functional projects.</li>
<li>Lead technical discussions, produce clear design documents, and guide the team on architectural patterns.</li>
<li>Troubleshoot production issues rapidly and improve system reliability through monitoring, logging, and error reduction.</li>
<li>Deliver high-impact backend features that directly support product growth, user engagement, and business goals</li>
</ul><h3 class="jobSectionHeader"> Skills, knowledge, and experience points required to unlock the role of Senior Django Engineer:</h3><ul>
<li>Expert-level proficiency in Django &amp; Django REST Framework, including ORM optimization, class-based views, and advanced API design.</li>
<li>Hands-on experience with asynchronous task processing, ideally Celery + Redis/RabbitMQ, and deep understanding of reliability patterns.</li>
<li>Ability to design scalable backend architectures, including caching layers, service boundaries, and performance bottleneck prevention.</li>
<li>Solid understanding of backend security practices, including authentication, authorization, rate-limiting, and secure data handling.</li>
<li>Proven track record of owning and delivering complex backend features, including writing technical designs and mentoring other engineers.</li>
<li>Good knowledge of English language (verbal and written)</li>
</ul>
Bonus points:<ul>
<li>
Experience with AWS or other cloud platforms</li>
<li>Knowledge of Docker or containerization</li>
<li>Exposure to event streaming technologies such as Apache Kafka</li>
</ul><h3 class="jobSectionHeader">&#65039; What your adventure will have in store:</h3>
<ul><li>You'll have the exhilarating opportunity to contribute to a product that is highly appreciated by users and the cybersecurity community at large.</li>
<li> You'll experience a highly supportive and caring environment, fostering growth, flexibility, and autonomy.</li>
<li> You'll embark on an exciting journey of continuous learning and problem-solving, leveling up as our organization grows.</li>
 Most importantly, you'll have a blast at HTB<li> because fun is an essential ingredient in our recipe for success! Just wait until you see our global meet-ups!</li>
</ul><h3 class="jobSectionHeader">The gems you&rsquo;ll be enjoying as a Senior Django Engineer:</h3><ul>
<li>25 annual leave days</li>
<li>Paid paternity leave</li>
<li>Dedicated budget for training and professional development, participation in conferences</li>
Full access to the Hack The Box lab offerings; so you can learn how to hack
<li>State-of-the-art equipment (mac, iPhone, and mobile plan)</li>
</ul>
Our benefits package is designed to provide strong support to our team, but it may vary depending on location and type of employment (e.g., UK, Greece, or engagement through an Employer
<h3 class="jobSectionHeader">&#65039; The Quest of Becoming Senior Django Engineer:</h3><ul>
<li>Level 1: To complete level one&rsquo;s objective, submit your application.</li>
<li>Level 2: Meet the Talent Acquisition team. Level&rsquo;s objective: highlight your past achievements, ambitions, and values.</li>
<li>Level 3: Meet the hiring team. Level&rsquo;s objective: connect with the hiring team and share with them your achievements.</li>
<li>Level 4: Meet the hiring team, once again, to explore your leadership mindset and values alignment with HTB.</li>
Level 5: Congratulations! Not many reach this level <li>. Level&rsquo;s objective: have a constructive, final conversation with senior leadership to explore the role and your future at HTB.</li>
<li>Level 6: You've officially received an offer from HTB! To complete the last level and the Quest, all you need to do is accept the offer.</li>
Quest complete. Congratulations, you&rsquo;re officially one of us Your next quest: complete the onboarding. 
<li>
</li>
</ul>Hack Your Career, Today. Join us in this epic adventure of cybersecurity at Hack The Box!<h3 class="jobSectionHeader">
ABOUT HACK THE BOX</h3>
Hack The Box is the leading cybersecurity readiness and upskilling platform, trusted by enterprises, government organizations, and MSSPs to build cyber resilience at scale. Through AI-enhanced intelligence, gamified labs, live-fire simulations, and the power of one of the world&rsquo;s largest cybersecurity communities, Hack The Box helps teams master offensive and defensive skills in real-world scenarios. Founded in 2017, Hack The Box has grown its global community of over 4 million members, helping organizations validate resilience, mitigate breach risk, and develop cyber talent. For more information, visit hackthebox.com
Rapidly growing its international footprint and reach, Hack The Box is headquartered in the UK, with additional offices in the US, Australia, and Greece.
 News &amp; Resources:<ul>
<li>
Get the most important updates on HTB&rsquo;s latest year!</li>
<li>We&rsquo;re incredibly proud to share that our headquarters in the UK, along with our entities in Greece and the US, have been certified as a Great Place to Work for three consecutive years (2023 - 2025).</li>
<li>In addition, our Greek entity has been recognized among the Best Workplaces in Greece (4th, 2nd, 3rd) and Europe (7th, 10th, 73rd) during this period &mdash; a testament to our strong culture and commitment to creating an exceptional employee experience!</li>
</ul>
Take a sneak peek at how it is to be part of HTB and our 2023 Global Retreat. Get more insights about our HTB culture and employee experience by visiting the &ldquo;about us&rdquo; section of our site, our career site, and Glassdoor.
At Hack The Box, we are committed to fostering a diverse, inclusive, and equitable workplace. We believe that diversity enriches our performance, services, and the communities we serve. As such, we ensure that all job applications are considered solely based on merit, skills, and qualifications. We do not discriminate on grounds of race, color, religion, gender, gender identity or expression, sexual orientation, national origin, genetics, disability, age, or veteran status. We are dedicated to providing a fair and respectful work environment that reflects our values.</div>

Senior Django Engineer

İSTANBUL CARE SAĞLIK TURİZMİ

&#304;&#351; a&ccedil;&#305;klamas&#305;Aranan Nitelikler:<ul><li>React.js ve Next.js konusunda g&uuml;&ccedil;l&uuml; bilgi ve proje deneyimi</li></ul><ul><li>HTML5, CSS3, JavaScript/ES6+ teknolojilerine hakimiyet</li></ul><ul><li>SEO uyumlu, performans odakl&#305; web uygulamalar&#305; geli&#351;tirme becerisi</li></ul><ul><li>Responsive tasar&#305;m, mobil uyumluluk ve modern UI/UX standartlar&#305;na h&acirc;kimiyet</li></ul><ul><li>Tercihen TailwindCSS, Bootstrap veya benzeri CSS framework&rsquo;lerinde deneyim</li></ul><ul><li>API entegrasyonu ve veri y&ouml;netimi konusunda tecr&uuml;be</li></ul><ul><li>Versiyon kontrol sistemleri (Git vb.) ile &ccedil;al&#305;&#351;ma al&#305;&#351;kanl&#305;&#287;&#305;</li></ul><ul><li>Backend (Python &amp; Django) bilgisi art&#305; de&#287;er olarak de&#287;erlendirilecektir</li></ul><ul><li>Tak&#305;m &ccedil;al&#305;&#351;mas&#305;na uyumlu, &ccedil;&ouml;z&uuml;m odakl&#305; ve detaylara &ouml;nem veren &ccedil;al&#305;&#351;ma stili</li></ul>Sundu&#287;umuz:<ul><li>Modern ve dinamik &ccedil;al&#305;&#351;ma ortam&#305;</li></ul><ul><li>Sa&#287;l&#305;k turizmi alan&#305;nda uluslararas&#305; projelerde yer alma f&#305;rsat&#305;</li></ul><ul><li>SEO uyumlu, y&uuml;ksek performansl&#305; web projelerinde sorumluluk alma</li></ul><ul><li>Uzun vadeli i&#351;birli&#287;i ve kariyer geli&#351;imi imk&acirc;n&#305;</li></ul>&#304;&#351; T&uuml;r&uuml;: Tam zamanl&#305;Maa&#351;: ayl&#305;k 60.000,00TRY veya &uuml;zeriBa&#351;vuru Sorular&#305;:<ul><li>Maa&#351; beklentiniz nedir?</li><li>&#304;stanbul Anadolu Yakas&#305;nda m&#305; ikamet ediyorsunuz?</li></ul>Deneyim:<ul><li>Frontend Developer: 2 y&#305;l (Zorunlu)</li></ul>

FRONTEND DEVELOPER

InoTrade

<div>
 
 
 Location:
 
 &Idot;stanbul/Ankara
 
 
 
 
 
 
 About InoTrade
 
 
 
 
 
 At InoTrade, we shape the future of global commerce by leading in AI-driven innovation. By combining advanced AI capabilities with deep industry expertise, we transform complexity into clarity and deliver solutions that drive meaningful, lasting impact.
 
 
 What makes this possible is our people. We bring together AI experts, engineers, researchers, and industry leaders who thrive on collaboration and curiosity. United by a passion for solving the toughest challenges, our team creates breakthroughs that push the boundaries of technology and business.
 
 
 
 
 
 Role
 
 
 
 
 
 
 We are seeking a highly skilled Full Stack Developer who will play a pivotal role across both frontend and backend development within our engineering team. We are looking for a colleague who takes genuine pride in crafting scalable, secure, and exceptionally high-performance applications, and who thrives on leveraging modern web technologies to build elegant, reliable, and future-ready systems.
 
 
 
 
 
 
 Responsibilities
 
 
 
 
 
 <ul>
 <li>
 End-to-end development and maintenance of web applications
 </li>
 <li>
 Designing and integrating backend APIs, and developing scalable, high-performance, and secure services
 </li>
 <li>
 Designing frontend interfaces using modern frameworks and ensuring an intuitive user experience
 </li>
 <li>
 Ensuring compliance with database design, query optimization, and management standards
 </li>
 <li>
 Maintaining code quality, test processes, continuous improvement, and documentation
 </li>
 <li>
 Maintaining, improving, and debugging existing projects
 </li>
 <li>
 Collaborating closely with UX/UI teams and AI/Machine Learning engineers to ensure system integration
 </li>
 <li>
 Contributing to DevOps processes (CI/CD, containerization, etc.)
 </li>
 <li>
 Staying up-to-date with the latest developments and best practices in Full Stack development technologies
 </li>
 </ul>
 
 
 
 
 
 Required Qualifications
 
 
 
 
 
 <ul>
 <li>
 Minimum 5 years of experience as a Full Stack Developer
 </li>
 <li>
 Proficiency in most of the following technologies:
 </li>
 </ul>
 
 Frontend: React, Vue, Angular, TypeScript, HTML5, CSS3
 
 
 Backend: Experience with at least one modern backend technology such as Node.js, .NET/C#, Java, Python
 
 
 Databases: PostgreSQL, MySQL, MongoDB
 
 
 DevOps: Docker, Kubernetes, CI/CD tools
 
 <ul>
 <li>
 Experience in building RESTful or GraphQL APIs
 </li>
 <li>
 Hands-on experience in unit testing processes
 </li>
 <li>
 Strong understanding of OOP principles, software design patterns, and Clean Architecture
 </li>
 <li>
 Practical knowledge of queue/messaging infrastructures such as RabbitMQ or Kafka
 </li>
 <li>
 Proficiency with Git version control
 </li>
 <li>
 Ability to write clean code and follow SOLID principles
 </li>
 <li>
 Experience working in Agile/Scrum environments
 </li>
 <li>
 Strong problem-solving skills and ability to work collaboratively in a team
 </li>
 </ul>
 
 
 
 
 
 Preferred Qualifications
 
 
 
 
 
 <ul>
 <li>
 Experience with cloud platforms (AWS, Azure, GCP)
 </li>
 <li>
 Experience working with microservice architectures
 </li>
 <li>
 Familiarity with test automation tools (Jest, Cypress, NUnit, etc.)
 </li>
 <li>
 Advanced knowledge of DevOps pipelines
 </li>
 </ul>
 
 
 
</div>

Full Stack Developer

Chefsdeal

Chef's Deal Restaurant Equipment Company in Downtown Nashville is seeking a Senior Backend PHP Developer for E&#8209;Commerce. If you're hard-working and dedicated, Chef's Deal is an excellent company for you. Apply today!You do not need to live in US for this job. We are seeking a specialist that lives in Turkey and can work at US Central time; Monday to Friday 8am. to 5pm.Interviews will be available immediately for qualified candidates.About the Role:We&rsquo;re building and scaling the backend of the Chef&rsquo;s Deal e&#8209;commerce platform, a high&#8209;traffic online store that combines Magento with a custom PHP framework. Our backend powers product catalogs, APIs, search, and integrations with payment providers and external services. We&rsquo;re looking for a Senior/Mid-Level Backend PHP Developer who can take ownership of complex features, improve performance, and help us evolve the platform for the future.Job Duties / Responsibilities:<ul><li>Maintain and extend backend features that power storefront APIs, product data, categories, and search.</li><li>Work with Magento data structures and synchronization flows (no deep Magento customization required).</li><li>Design and tune Elasticsearch indices and queries for fast, relevant product search and listings.</li><li>Integrate and maintain payment gateways (Stripe, PayPal).</li><li>Work with AWS services (S3, SDK integrations) for media and asset storage.</li><li>Improve performance and reliability of background jobs and indexing pipelines.</li><li>Troubleshoot production issues using logs and monitoring tools (Sentry) and propose resilience improvements.</li><li>Performs other duties as assigned</li></ul>Qualifications:<ul><li>Strong PHP 8.x experience with Composer&#8209;based dependency management.</li><li>Familiarity with mainstream frameworks (Laravel, Symfony) and ability to work with custom frameworks.</li><li>Deep SQL/MySQL knowledge (schema design, queries, migrations, performance tuning).</li><li>Experience with Elasticsearch (indexing, analyzers, queries, tuning).</li><li>Experience with Redis for caching and sessions.</li><li>Familiarity with AWS SDK/S3 and file storage integrations.</li><li>Experience with payment gateway integrations.</li><li>Comfortable with Docker for local development.</li><li>Solid understanding of testing (PHPUnit), Git workflows, and CI/CD pipelines</li></ul>Additional Skills (Good to have):<ul><li>Exposure to Magento product/catalog schemas.</li><li>Experience with Kubernetes deployments.</li><li>Background in large&#8209;scale data processing or long&#8209;running console tasks.</li><li>Prior experience with e&#8209;commerce platforms and checkout/payment flows.</li></ul>Soft Skills :<ul><li>Clear communicator who can explain technical trade&#8209;offs.</li><li>Strong problem&#8209;solver with debugging and production triage skills.</li><li>Team player who shares knowledge and supports others.</li><li>Self&#8209;driven, organized, and able to own features end&#8209;to&#8209;end.</li><li>Pragmatic and outcomes&#8209;oriented, balancing delivery with technical quality</li><li>Fluent in English</li></ul>Why Join Us :<ul><li>Work on a high&#8209;impact e&#8209;commerce platform with real&#8209;world scale.</li><li>Collaborate with a skilled, supportive engineering team.</li><li>Competitive salary and benefits.</li><li>Flexible working arrangements.</li><li>Opportunities for growth in modern backend, cloud, and search technologies.</li></ul>Position: Full time, RemoteExperience Level: Senior / Mid-LevelSalary: Between 1500 and 2000 USD (depending on the experience)Job Types: Full-time, Contract, PermanentPay: 63,500.00TRY - 85,000.00TRY per month

Senior/Mid-level Backend PHP Developer E‑Commerce

Sezzle

<div>The salary range for this role is $4,600 - $9,500 per month (Gross in USD)

About Sezzle:

With a mission to financially empower the next generation, Sezzle is revolutionizing the shopping experience beyond payments, blending cutting-edge tech with seamless, interest-free installment plans that make shopping smarter and more accessible. We're not just transforming payments; we're redefining how people discover, interact with, and purchase the things they love while driving real impact on merchant sales through increased conversions and higher order values. As we continue to shape the future of fintech and retail, we're building an innovative, dynamic team passionate about creating more than just a transaction but a truly unique shopping journey. If you're excited about pushing boundaries in tech and delivering a game-changing experience for consumers and merchants alike, come join us at Sezzle and help create the future of shopping!

About the Role:

We are seeking a talented and motivated Senior Mobile Engineer who is best in class with a high IQ plus a high EQ. This role presents an exciting opportunity to thrive in a dynamic, fast-paced environment within a rapidly growing team, with abundant prospects for career advancement.

Compensation

The compensation range for the role is as follows:
<ul>
<li>4,600 - 9,500 USD Monthly</li>
</ul>
What You'll Do:
<ul>
<li>Help own and build out new features within our cross-platform TypeScript React Native app, and Golang backend APIs.</li>
<li>Manage our releases, using tools like cohorting, feature flags, and app-store infrastructure to ensure a safe rollout to our millions of active users.</li>
<li>Maintain a strong working relationship with product, design, and the business to ensure stakeholder needs are being evaluated and met.</li>
<li>Work with the team to continuously build clean, scalable, robust, and testable code.</li>
<li>Develop a deep working knowledge of your application, data domain, and KPIs.</li>
</ul>
What We Look For:
<ul>
<li>5+ years of professional mobile development experience, with at least 2+ years in React Native or similar technology such as Flutter.</li>
<li>Experience working with native code on iOS (Swift/ObjC) and Native Android (Kotlin/Java).</li>
<li>Experience developing and delivering a mobile application to Apple and Google's mobile app stores.</li>
<li>Deep understanding of React Native architecture, hooks, context, navigation patterns, and performance optimization.</li>
<li>Strong familiarity with unit testing, integration testing, and E2E testing (Jest, React Native Testing Library, Detox, Appium, etc.).</li>
<li>Ability to lead features end-to-end &mdash; from requirements, design, implementation, deployment, monitoring, and improvement.</li>
<li>Experience mentoring junior or mid-level engineers.</li>
<li>Capable of performing high-quality code reviews with focus on maintainability, clarity, and best practices.</li>
<li>Drives technical decisions, proposes improvements, and elevates code quality across the team.</li>
<li>Works well with product managers, designers, backend teams, and QA.</li>
<li>Bachelor's degree in computer science</li>
<li>Knowledge of mobile CI/CD pipelines (Fastlane, Bitrise, GitHub Actions, etc.).</li>
</ul>
Preferred Knowledge and Skills:
<ul>
<li>Knowledgeable in writing automated tests for applications (unit, integration, end-to-end), and implementing them in a CI environment.</li>
<li>Ability to solve problems with backend-focused languages like Go, Python, Java or similar.</li>
<li>Familiarity with typical microservice architecture composed of HTTP APIs.</li>
<li>Experience working with native code on iOS, Android.</li>
</ul>
About You:
<ul>
<li><ul><li>You have relentlessly high standards - many people may think your standards are unreasonably high. You are continually raising the bar and driving those around you to deliver great results. You make sure that defects do not get sent down the line and that problems are fixed so they stay fixed.</li>
<li>You're not bound by convention - your success&mdash;and much of the fun&mdash;lies in developing new ways to do things</li>
<li>You need action - speed matters in business. Many decisions and actions are reversible and do not need extensive study. We value calculated risk-taking.</li>
<li>You earn trust - you listen attentively, speak candidly, and treat others respectfully.</li>
<li>You have backbone; disagree, then commit - you can respectfully challenge decisions when you disagree, even when doing so is uncomfortable or exhausting. You have conviction and are tenacious. You do not compromise for the sake of social cohesion. Once a decision is determined, you commit wholly.</li>
</ul>
</li></ul>Sezzle's Technology Stack:
<ul>
<li>Languages: Golang, Typescript, Python</li>
<li>Frontend: Typescript - React and React Native</li>
<li>Backend: Golang</li>
<li>Database: MySQL, Postgres, Elasticsearch</li>
<li>DevOps &amp; Cloud: AWS, Kubernetes</li>
<li>Version Control: Git</li>
<li>CI/CD: Gitlab</li>
<li>Testing: Developer-driven, focus on automated unit, integration, and end-to-end tests</li>
<li>Sezzle is focused on using open source, and we build what we can before buying!</li>
</ul>
What Makes Working at Sezzle Awesome?

At Sezzle, we are more than just brilliant engineers, passionate data enthusiasts, out-of-the-box thinkers, and determined innovators; we are skilled musicians, yogis, cyclists, chefs, golfers, dog-lovers, and rock-climbers. We believe in surrounding ourselves with not only the best and the brightest individuals, but those that are unique and purpose-driven in all that they do. Our culture is not defined by a certain set of perks designed to give the illusion of the traditional startup culture, but rather, it is the visible example living in every employee that we hire.

#Li-remote #Full-time</div>

Senior Mobile Engineer

WALIRON

<div>
 
 About Waliron
 
 
 Waliron is building a next-generation
 
 payment orchestration platform
 
 for merchants, PSPs, and fintechs across Turkey, MENA, and Europe.
 
 
 We are developing a fully modular, scalable and event-driven infrastructure including:
 
 <ul>
 <li>
 Smart Routing
 </li>
 <li>
 Retry &amp; Fallback Engine
 </li>
 <li>
 PSP Connector Framework
 </li>
 <li>
 Token Vault
 </li>
 <li>
 Rule Engine (no-code)
 </li>
 <li>
 Unified Payment Response Model
 </li>
 <li>
 Webhook/Event Pipeline
 </li>
 <li>
 Dispute Automation
 </li>
 <li>
 Merchant Dashboard
 </li>
 <li>
 Observability Layer
 </li>
 </ul>
 
 
 
 
 Our goal is simple:
 
 
 
 To become the leading orchestration layer in the region, similar to Stripe/Adyen-level infrastructure.
 
 
 
 We already have a strong engineering shortlist and are now hiring the
 
 architect who will design the entire system
 
 .
 
 
 
 
 
 Role: Senior / Principal Payment Architect
 
 
 You will be the
 
 architectural owner
 
 of Waliron&rsquo;s payment infrastructure and orchestration logic.
 
 
 Not a &ldquo;developer&rdquo; role &mdash;
 
 
 This is a
 
 system designer, framework builder, and technical decision-maker
 
 role.
 
 
 You will work closely with the founder, Backend Lead, and senior engineers to define:
 
 <ul>
 <li>
 Payment Routing Engine
 </li>
 <li>
 PSP Integration Framework
 </li>
 <li>
 Retry &amp; Fallback Architecture
 </li>
 <li>
 Rule Engine Evaluation Pipeline
 </li>
 <li>
 Unified Payment Response Layer
 </li>
 <li>
 Token Vault Architecture
 </li>
 <li>
 Transaction Lifecycle
 </li>
 <li>
 Event-Driven Microservice Topology
 </li>
 <li>
 Idempotency &amp; Concurrency Control
 </li>
 <li>
 High-Throughput Processing Pipelines
 </li>
 </ul>
 
 
 
 
 What You Will Do
 
 <ul>
 <li>
 Design the overall payment orchestration architecture
 </li>
 <li>
 Define routing strategies (latency, SLA, BIN, fallback rules)
 </li>
 <li>
 Build PSP connector standards &amp; integration patterns
 </li>
 <li>
 Establish transaction timelines (auth, capture, refund, cancel, dispute)
 </li>
 <li>
 Ensure idempotency &amp; consistency
 </li>
 <li>
 Optimize performance for high TPS workloads
 </li>
 <li>
 Collaborate closely with senior engineers (Node.js / Go / .NET / Java)
 </li>
 <li>
 Lead architectural documentation &amp; technical standards
 </li>
 <li>
 Own system reliability, scalability and observability
 
 </li>
 </ul>
 
 Required Experience
 
 
 We&rsquo;re looking for someone who has
 
 direct experience
 
 in ANY of the following areas:
 
 <ul>
 <li>
 Craftgate, Trendyol Payments, PayCore, Papara, Paycell, Param, iyzico integrations
 </li>
 <li>
 PSP integration frameworks
 </li>
 <li>
 Payment routing / switching systems
 </li>
 <li>
 Payment lifecycle (Auth &rarr; Capture &rarr; Refund &rarr; Cancel &rarr; Dispute)
 </li>
 <li>
 Microservices (Node.js / Go / Java / .NET Core)
 </li>
 <li>
 Message queues (Kafka / RabbitMQ / SQS/SNS)
 </li>
 <li>
 Event-driven architecture
 </li>
 <li>
 Tokenization / 3D Secure / Card flows
 </li>
 <li>
 PCI-DSS awareness
 </li>
 <li>
 High-availability systems
 
 </li>
 </ul>
 
 Nice to Have
 
 <ul>
 <li>
 Experience in scaling high-throughput systems
 </li>
 <li>
 Interest in distributed systems and concurrency
 </li>
 <li>
 Experience in fintech, payment infrastructure, or orchestration platforms
 
 </li>
 </ul>
 
 What We Offer
 
 <ul>
 <li>
 Architect-level ownership
 </li>
 <li>
 Team of strong senior backend engineers
 </li>
 <li>
 A rare opportunity to design an orchestration platform from scratch
 </li>
 <li>
 Direct work with the founder &amp; engineering lead
 </li>
 <li>
 Growth path toward
 
 Chief Architect
 
 
 </li>
 </ul>
 Apply
 
 Send your CV or LinkedIn profile to: career@waliron.io
 
 
 
 
 
 
 
</div>

Senior / Principal Payment Architect (PSP Integration & Orchestration)

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