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lead backend engineer

Commencis

<div><div>We are looking for a highly motivated and experienced <b>Lead Backend Engineer</b> to join our team.</div>
<div></div>
<div><b>Lead Backend Engineer</b> is responsible for designing, developing, and maintaining scalable backend systems that power our products and services. In this role, you will translate business and product requirements into robust technical solutions, ensuring high performance, reliability, and security across backend services.</div>
<div></div>
<div>As a technical leader, you will collaborate closely with cross-functional teams including frontend developers, DevOps engineers, product managers, and solution architects to design and implement efficient, scalable, and maintainable backend architectures.</div>
<div></div>
<div><b>If you are curious by nature, adaptive, collaborative, and always one step ahead, then join us and be a Commencer!</b></div>
<h3 class="jobSectionHeader"><b>Responsibilities
</b></h3><ul><li>Design, implement, and operate cloud-native AI/ML services that are secure, reliable, and cost-efficient ensuring that they meet the business objectives and adhere to service level agreements (SLA).</li>
<li>Deploy and maintainAI applications on cloud- architecture.</li>
<li>Build retrieval-augmented generation (RAG) stacks: embeddings, vector stores, chunking, and evaluation.</li>
<li>Create MLOps foundations: experiment tracking, model registry, CI/CD for data &amp; models, and Infrastructure-as-Code.
</li><li>Investigate new techniques, tools, and methods that might increase efficiency among engineering &amp; technology and cloud teams, as well as leading execution processes of topics evaluated &amp; planned for roll-out.</li>
<li>Collaborate with other technical leaders and business stakeholders to align all constraints and come up with solutions regarding project/product/initiative outputs.</li>
<li>Be accountable for the reliability and security of cloud infrastructure and services.</li>
<li>Provide visibility of performance, cost, and the security of cloud infrastructure and services.</li>
<li>Drive continuous improvement, continuous delivery, and lean practices within the cloud team.</li>
<li>Keep up to date on modern technologies and trends and advocate for their inclusion within products when it makes sense.</li>
<li>Identify emerging technology solutions that reduce costs, increase efficiencies, enhance capabilities, reduce risk and improve security.</li>
<li>Ensure that all cloud technology applications create a positive customer experience.</li>
</ul><h3 class="jobSectionHeader"><b>Qualifications
</b></h3><ul><li>BS/MS degree in Computer Science, Engineering or a related subject.
</li><li>Proven hands-on software engineering experience.
</li><li>Strong experience in Java development.
</li><li>Strong experience with Spring Framework, preferably Spring Boot.
</li><li>Hands-on experience in designing and developing enterprise-grade backend applications.
</li><li>Solid understanding of microservice architecture and distributed systems.
</li><li>Experience with event-driven architecture and asynchronous integration patterns.
</li><li>Strong knowledge of scalable, resilient and high-availability system design.
</li><li>Solid understanding of object-oriented analysis and design using common design patterns.
</li><li>Experience with RESTful APIs and backend integration patterns.
</li><li>Experience leading highly skilled software engineers and supporting team growth.
</li><li>Ability to coordinate effectively across multiple teams and stakeholders.
</li><li>Strong communication skills in English, both written and spoken.
</li><li>Team Lead and Agile Scrum experience is a strong plus.
</li>
</ul><div></div><h3 class="jobSectionHeader"><b>Preferred Qualifications
</b></h3><ul><li>Experience with containerized environments and CI/CD pipelines.
</li><li>Experience with monitoring, logging and observability tools in distributed systems.
</li><li>Familiarity with cloud-native architectures and modern backend infrastructure.
</li><li>Experience in performance optimization, system reliability and production support.
</li></ul><div><b>Why Commencis?</b></div>
<div></div>
<div>We want people to thrive at Commencis. Here&rsquo;s what Commencers like about working here:</div>
<div></div>
<div><b>Competitive Compensation &amp; Benefits:</b> We offer a competitive salary, private health insurance, pension and retirement plans through a company-backed pension system, meal card, commute compensation, work-from-home support, and a paid birthday off.</div>
<div></div>
<div><b>Happier Weekdays:</b> We offer flexible working hours, including a remote working option. Enjoy online events, guest speakers, office refreshments, a meeting-light culture, and many more perks to enhance your weekdays.</div>
<div></div>
<div><b>Never Stop Learning:</b> We support learning and development programs for almost anything. Additionally, we provide access to leading online e-learning platforms like Udemy and various libraries.</div>
<div></div>
<div><b>Community &amp; Socials:</b> We are a tight-knit community that loves gathering together. Our social activities include happy hours, workshops, a New Year party, breakfast &amp; lunch get-togethers, movie nights, and our Summer Festival.</div>
<div></div>
<div><b>Open Culture:</b> We maintain a flat organizational structure with a culture of direct and open communication. We value Commencers&rsquo; voices and address any suggestions and questions you may have.</div><br>
<div></div>
<div></div>
<div><b>About Commencis</b></div>
<div></div>
<div>Join us in paving the way for a thriving digital society!</div>
<div></div>
<div>Commencis has more than two decades of expertise in the world of experience design, software engineering and cloud technologies. Our products and solutions are used by leading brands in financial services, insurance, airlines and retail in more than 20 countries.</div>
<div></div>
<div>We help our clients around the globe to commence their next evolution and pave the way for a thriving digital society. We love discovering what&rsquo;s next. We value collaboration, curiosity, and an open mindset at work.</div>
<div></div>
<div>If you share the same passion with our fellow Commencers, then let us unleash your world-class potential!</div>
<div></div>
<div><b>We will process your personal data as part of our recruitment procedures. To find out more, please consult our </b><b>Candidate Privacy Notices</b><b>.</b></div>
<p>
We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.</p></div>

Lead Backend Engineer

Hack The Box

<div>Ready to embark on the quest of joining Hack The Box?<p>
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!
</p><p></p><b>✨The core mission of the Senior Django Engineer:</b><p>
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.
</p><p>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.</p><p>
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.</p><p><b>
Location &amp; Work Mode:</b></p><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><b>
The fellowship you&rsquo;ll be joining:</b><p>
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.</p><ul><li><b>️ Technology tools &amp; weapons you&rsquo;ll be using:</b></li></ul><ul><li>
Django Framework (Python language)</li><li>
Docker</li><li>
Apache Kafka</li><li>
Redis</li><li>
Git</li></ul><b>
Interesting resources you should check:</b><ul><li>
Take a look at LetsDefend Website</li><li>
Hack The Box + LetsDefend: Shaping the future of community-led cyber readiness</li></ul>
<b>The adventures that await you after becoming Senior Django Engineer:</b><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><b>
Skills, knowledge, and experience points required to unlock the role of Senior Django Engineer:</b><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><p>
Bonus points:</p><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>
️ What your adventure will have in store:<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><li>
Most importantly, you'll have a blast at HTB because fun is an essential ingredient in our recipe for success! Just wait until you see our global meet-ups!</li></ul>
The gems you&rsquo;ll be enjoying as a Senior Django Engineer:<ul><li>
25 annual leave days</li><li>
Paid paternity leave</li><li>
Dedicated budget for training and professional development, participation in conferences</li><li>
Full access to the Hack The Box lab offerings; so you can learn how to hack
</li><li>State-of-the-art equipment (mac, iPhone, and mobile plan)</li></ul><p>
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
</p><b>️ The Quest of Becoming </b>Senior Django Engineer:<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><li>
Level 5: Congratulations! Not many reach this level . 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><li>
Quest complete. Congratulations, you&rsquo;re officially one of us Your next quest: complete the onboarding.</li></ul><p><b><br>
Hack Your Career, Today. Join us in this epic adventure of cybersecurity at Hack The Box!
</b></p>ABOUT HACK THE BOX<p>
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</p><p>
Rapidly growing its international footprint and reach, Hack The Box is headquartered in the UK, with additional offices in the US, Australia, and Greece.</p><p><b>
News &amp; Resources:</b></p><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><p></p><p>
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.</p><p></p><p><i>
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.</i></p></div>

Senior Django Engineer

<div><div><p>We are looking for a highly experienced and technically strong<b> Software Architect </b>to<b> </b>join our backend team.<br>
<br>
<b>Software Architect</b> is responsible for designing and evolving the technical architecture of backend services, with a primary focus on Java, Spring Boot, distributed systems, and domain-oriented design. In this role, you will translate complex business and product requirements into scalable, maintainable, and high-quality architectural solutions, ensuring long-term sustainability, performance, and reliability across systems.<br>
<br>
As a Software Architect, you will collaborate closely with engineering teams, product managers, QA, DevOps, and peer architects to establish architectural standards, guide best practices, and ensure alignment across teams. You will drive the design of modular and scalable backend systems, oversee service architecture, APIs, data flows, and integration patterns, and ensure that software solutions are secure, observable, and aligned with both business and engineering objectives.</p>
<p><b>
If you are curious by nature, adaptive, collaborative, and always one step ahead, then join us and be a Commencer!</b></p>
</div>
<h3 class="jobSectionHeader"><b>Responsibilities
</b></h3><ul><li>Providing active hands-on architectural guidance and leadership through the entire lifecycle of backend products and services</li>
<li>Designing backend architectures using Java, Spring Boot, and related technologies in alignment with scalability, maintainability, performance, and security goals</li>
<li>Defining and evolving domain structures, bounded contexts, service decomposition strategies, and modular architecture approaches including modular monolith and microservices where appropriate</li>
<li>Collaborating closely with other architects, engineering managers, and development teams across the organization in architecting and delivering robust backend solutions</li>
<li>Structuring and delivering technical documentation for HLDs, architecture decision records, solution designs, analysis inputs, API contracts, sequence diagrams, and backend design artifacts, and establishing standard practices for co-workers to adapt easily</li>
<li>Investigating and assessing emerging technologies, backend frameworks, and architectural patterns to determine the best approach for product and platform needs</li>
<li>Defining non-functional requirements from availability, scalability, security, observability, extensibility, and operational support perspectives, and designing backend solutions to meet those requirements</li>
<li>Supporting teams in troubleshooting system-level backend, integration, performance, data consistency, and production issues</li>
<li>Designing and guiding API-first, event-driven, and asynchronous integration patterns between internal and external systems</li>
<li>Driving architectural decisions for distributed systems including resilience, retries, idempotency, fault tolerance, transaction boundaries, caching, and messaging patterns</li>
<li>Reviewing and improving service boundaries, backend code structure, data access patterns, deployment architecture, and technical debt areas</li>
<li>Developing and leading proof-of-concept projects for backend frameworks, platform capabilities, and architectural improvements</li>
<li>Driving discussions with senior co-workers regarding trade-offs, best practices, project delivery risks, and backend modernization strategies</li>
<li>Cross-training peers and mentoring teammates on software design principles, backend architecture patterns, and engineering standards</li>
<li>Conducting code reviews and design reviews, and providing feedback to team members with a focus on backend quality attributes and architectural sustainability</li>
<li>Assisting in technical audits and ensuring audit recommendations are implemented in line with secure software development and platform standards</li>
</ul><h3 class="jobSectionHeader"><b>Qualifications
</b></h3><div><ul><li>BSc/MSc degree in Computer Engineering, Software Engineering, or a related field</li>
<li>8+ years of experience in backend software development, with strong hands-on experience in Java and Spring Boot</li>
<li>3+ years of experience in design and implementation of complex distributed backend systems and software architectures</li>
<li>2+ years of experience in a similar position guiding a cross-functional project or product team</li>
<li>Strong experience in backend service design, API architecture including REST, GraphQL, and gRPC, service-to-service communication, and integration patterns</li>
<li>Strong knowledge of software architecture patterns such as layered architecture, hexagonal architecture, clean architecture, modular monoliths, and microservices</li>
<li>Experience with domain-driven design, domain modeling, and designing systems across different domain structures and business capabilities</li>
<li>Experience with containerization and orchestration frameworks such as Docker and/or Kubernetes</li>
<li>Working knowledge of application and system availability, scalability, observability, and distributed data platforms</li>
<li>Expertise in backend performance optimization, transaction management, concurrency handling, and scalable system design</li>
<li>Experience with relational database design, SQL optimization, and data consistency patterns, with additional familiarity in non-relational and NoSQL databases</li>
<li>Experience with messaging and streaming technologies such as Kafka, RabbitMQ, or similar platforms</li>
<li>Expert-level understanding of CI/CD principles, knowledge of various tools, and strong focus on engineering quality gates and delivery practices</li>
<li>Knowledge of cloud services, especially AWS and related AWS services</li>
<li>Strong understanding of secure backend development practices including authentication, authorization, secure communication, and secrets/configuration management</li>
<li>Strong unit testing, integration testing, debugging, and root cause analysis skills</li>
<li>Prior experience with SCRUM/Agile methodologies</li>
</ul></div><div><b>Why Commencis?</b></div>
<div></div>
<div>We want people to thrive at Commencis. Here&rsquo;s what Commencers like about working here:</div>
<div></div>
<div><b>Competitive Compensation &amp; Benefits:</b> We offer a competitive salary, private health insurance, pension and retirement plans through a company-backed pension system, meal card, commute compensation, work-from-home support, and a paid birthday off.</div>
<div></div>
<div><b>Happier Weekdays:</b> We offer flexible working hours, including a remote working option. Enjoy online events, guest speakers, office refreshments, a meeting-light culture, and many more perks to enhance your weekdays.</div>
<div></div>
<div><b>Never Stop Learning:</b> We support learning and development programs for almost anything. Additionally, we provide access to leading online e-learning platforms like Udemy and various libraries.</div>
<div></div>
<div><b>Community &amp; Socials:</b> We are a tight-knit community that loves gathering together. Our social activities include happy hours, workshops, a New Year party, breakfast &amp; lunch get-togethers, movie nights, and our Summer Festival.</div>
<div></div>
<div><b>Open Culture:</b> We maintain a flat organizational structure with a culture of direct and open communication. We value Commencers&rsquo; voices and address any suggestions and questions you may have.</div><br>
<div></div>
<div></div>
<div><b>About Commencis</b></div>
<div></div>
<div>Join us in paving the way for a thriving digital society!</div>
<div></div>
<div>Commencis has more than two decades of expertise in the world of experience design, software engineering and cloud technologies. Our products and solutions are used by leading brands in financial services, insurance, airlines and retail in more than 20 countries.</div>
<div></div>
<div>We help our clients around the globe to commence their next evolution and pave the way for a thriving digital society. We love discovering what&rsquo;s next. We value collaboration, curiosity, and an open mindset at work.</div>
<div></div>
<div>If you share the same passion with our fellow Commencers, then let us unleash your world-class potential!</div>
<div></div>
<div><b>We will process your personal data as part of our recruitment procedures. To find out more, please consult our </b><b>Candidate Privacy Notices</b><b>.</b></div>
<p>
We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.</p></div>

Software Architect (Backend)

Bitfinex

<div><h4 class="jobSectionHeader"><b>The Original Bitcoin Exchange</b></h4><p>
Inspired by Bitcoin's vision of financial freedom, we are committed to empowering individuals to transact and connect seamlessly across the globe. From the early days of the Bitcoin revolution, our mission has been to champion freedom through innovative, reliable, and accessible technology&mdash;ensuring that everyone, everywhere, has the tools to participate in a truly open and borderless world.
</p><p></p><p>We are driven by a relentless pursuit of innovation and financial empowerment. By prioritizing education and delivering a cutting-edge platform, we enable users to seamlessly buy, hold, and trade digital assets with confidence. As the digital asset landscape rapidly evolves, we stay ahead&mdash;offering state-of-the-art trading services that empower both individuals and global liquidity providers. Our forward-thinking, agile approach ensures that financial freedom is not just a vision, but a reality for all.</p><p></p><p>
Our team, composed of visionary individuals with practical expertise, focuses on crafting solutions to the market's toughest challenges. Despite our global presence and impact, we maintain a small, technology-focused core, fostering a culture of collaboration and innovation.
</p><p></p><p>We value integrity and autonomy, empowering our team to contribute from concept to launch. Driven by a passion for lifelong learning and a commitment to advancing freedom, we prioritize high-caliber products and services, with a proven track record of innovation that draws on the dexterity of our teams.</p><p></p><h4 class="jobSectionHeader"><b>
Why Join Us?</b></h4><p></p><p><b>
Innovation</b>
</p><p>At Bitfinex, we merge technology and skill to create an environment where your involvement isn&rsquo;t just appreciated&mdash;it&rsquo;s pioneering the future and pushing boundaries in finance. Our culture values bold creativity, a passion for technology, and a deep belief in Financial Freedom.
</p><p></p><p><b>Flexibility &amp; Global Reach</b>
</p><p>We believe in trust, autonomy, and results&mdash;our team operates remotely, ensuring you work from anywhere while collaborating with some of the best talents across the world. We thrive on innovation, autonomy, and breaking new ground.
</p><p></p><p><b>Fast-Paced &amp; Impactful</b>
</p><p>Much like the crypto industry itself, our projects move fast, break new ground, and make an impact. Your contributions reach our global audience, shaping the narrative of a decentralized future.
</p><p></p><p><b>A Team that Thrives on Collaboration</b>
</p><p>We blend seasoned experts with fresh creative minds, ensuring constant innovation, mentorship, and a dynamic work environment that keeps you at the forefront of achieving your goals. We see integrity and standing up for what is right as the most important qualities.
</p><p></p><p><b>Grow with the Best
</b></p><p>At Bitfinex, we&rsquo;re committed to continuous learning&mdash;whether through technological advancements, creative workshops, or mentorship from leading professionals in the industry.</p><p></p><p>
If you&rsquo;re excited about partaking in shaping the narrative of decentralized finance, you&rsquo;ll feel right at home</p><p></p><p><b>
We&rsquo;re looking for:</b> <b>Senior Backend Developer
</b></p><p></p><h4 class="jobSectionHeader"><b>The Role:</b></h4><p><br>
As a senior Backend Developer, you will be a part of the team that works on the development of the backend components of all Bitfinex Services (main trading application, Lightning Network support, Blockchain integrations, &hellip;.). This includes:</p><p></p><ul><li><b>
New Products and Features</b> - Bitfinex continuously strives to create innovative new features in order to provide the most professional trading experience for customers. These are developed and deployed using agile methodologies, to ensure the user experience remains the best in the industry.</li><li><b>
Scalability</b> - all backend services that power Bitfinex platform must remain effortlessly smooth, responsive, and real-time for customers as the platform continues to scale to accommodate new user growth. A good example are the renown Bitfinex API, the most solid, low-latency and complete in our industry.</li><li><b>
Security</b> - Bitfinex makes Security its most important feature. The Backend Development team is responsible for building all the API services and backend processes with the highest security principles and standard, in order to protect the safety of the entire user base.</li></ul><p></p><h4 class="jobSectionHeader"><b>
What You Bring to the Table:</b></h4><ul><li>
Exceptional Node/JavaScript skills</li><li>
Familiar with microservices architecture</li><li>
Have actively participated in the development of a complex platform</li><li>
Good experience in interacting with databases (MySQL, MongoDB)</li><li>
Ability to quickly learn new technologies</li><li>
Good understanding of security practices</li></ul><p></p><h4 class="jobSectionHeader"><b>
Other Valuable Skills:</b></h4><ul><li>
Experience with blockchain integration</li><li>
Comfortable with high-availability concepts</li><li>
Ruby, Rust or C++ skills are a plus</li><li>
Other technologies of interest: Message queues (Redis), Caches and Job Queues</li></ul><p></p><h4 class="jobSectionHeader"><b>
What We Offer:</b></h4><ul><li>
Flexible Work &amp; Remote-Friendly Culture</li><li>
Mentorship &amp; Growth</li><li>
Competitive Pay</li><li>
Career Development Opportunities</li><li>
Supportive Team Environment</li><li>
Learning &amp; Knowledge Sharing</li><li>
Team-Building Activities</li><li>
Social activities (online &amp; in-person)</li><li>
A collaborative environment where your creativity will have a direct impact on the brand&rsquo;s narrative</li></ul><p></p><p><b>
Ready to join us in bringing Financial Freedom to all?</b></p><p><br>
If you&rsquo;re a visionary who thrives at the intersection of technology, knowledge and innovation, we want to hear from you!</p><p></p><p><b><i>
Recruitment Data &amp; Security Disclaimer</i></b></p><p><i>
As part of the hiring process at Bitfinex, we collect personal data such as your name, contact details, location, job preferences, education and employment history, and other information you voluntarily provide. This data is used solely for recruitment purposes, processed in accordance with applicable global data protection laws, including the General Data Protection Regulation (GDPR) and the California Consumer Privacy Act (CCPA), and retained only for as long as necessary to fulfil its purpose.
</i></p><p></p><p><i>All assessments and recruitment-related communications are conducted exclusively through official Bitfinex email addresses (e.g., </i><i>firstname.lastname@bitfinex.com</i><i>). Bitfinex does not use unofficial channels (such as WhatsApp, Telegram, or SMS) for recruitment communication and does not distribute assessments or sensitive links via those means.</i></p><p></p><p><i>
As part of our secure and compliant recruitment process, we may use approved third-party platforms to facilitate candidate assessments. For more information, please refer to our </i><i>Candidate Privacy Notice and Interview Recording Consent</i><i>. All candidates have the right to access, correct, or delete their personal data and to withdraw consent at any time, where applicable.</i></p><p></p><p><i>
Bitfinex will never request payments, financial information, or personal banking details at any stage of the recruitment process.</i></p><p><i>
If you receive a suspicious request, wish to exercise your data privacy rights, or have further inquiries regarding the legal aspects of the process, contact </i>privacy@bitfinex.com<i>. </i><i>Please note this inbox is intended for privacy concerns and reports only; any other communications will not be processed</i><i>.</i></p><p></p><p><b><i>
Equal Opportunity Statement</i></b></p><p><i>
At Bitfinex, we're committed to equitable opportunities. We do not discriminate based on race, religion, gender, age, disability, sexual orientation, gender identity, or any other protected status. This commitment applies across all stages of recruitment and contractual relationships.</i></p></div>

Senior Backend Developer - Node.js (Fully Remote, Worldwide)

ING Türkiye

<div>
 <p>
  At ING we encourage you to `
  <strong>
   Do Your Thing
  </strong>
  ` to do more of what you love. We&rsquo;re on a journey that&rsquo;s centered around our customers, powered by technology and digital environment, driven by smart, determined people. Our customers feel our people are empowering them to stay a step ahead in life and in business. We&rsquo;re proud of that!
 </p>
 <p>
  We want you to discover and develop yourself while developing others, be creative, be successful, excel at your career life, work agile so new ideas come to life faster! Interested?
 </p>
 <p>
  <br/>
 </p>
 <p>
  Join our
  <strong>
   Mobile Team
  </strong>
  as
  <strong>
   QA Automation and Technical Analysis Specialist
  </strong>
  and discover the life at ING. You may work for creating the institution which will provide the best digital employee experience.
 </p>
 <p>
  <br/>
 </p>
 <p>
  If you think you have most of the following
  <strong>
   qualifications
  </strong>
  ;
 </p>
 <p>
  <br/>
 </p>
 <ul>
  <li>
   Bachelors degree in Engineering, Mathematics or Statistics
  </li>
  <li>
   Minimum
   <strong>
    4 years
   </strong>
   of experience
   <strong>
    analysis, documentation and testing
   </strong>
  </li>
  <li>
   <strong>
    Hands-on experience in test automation is a MUST
   </strong>
   (Appium preferred; Selenium, Gauge, Playwright or similar tools are acceptable)
  </li>
  <li>
  </li>
  <li>
   Proficient in
   <strong>
    SQL
   </strong>
   queries and preferably experience on
   <strong>
    ORACLE
   </strong>
   database
  </li>
  <li>
   Experience
   <strong>
    in performance testing
   </strong>
   or ability to design performance-related scenarios
  </li>
 </ul>
 <p>
  <br/>
 </p>
 <ul>
  <li>
   Experience
   <strong>
    in Backend, API and Mobile testing
   </strong>
   (Postman, Soap UI or similar tools)
  </li>
 </ul>
 <p>
  <br/>
 </p>
 <ul>
  <li>
   Ability to use
   <strong>
    logs, metrics, and telemetry
   </strong>
   (observability thinking) to validate issues or test results
  </li>
 </ul>
 <p>
  <br/>
 </p>
 <ul>
  <li>
   Experience in
   <strong>
    Agile / Scrum
   </strong>
   environments
  </li>
 </ul>
 <p>
  <br/>
 </p>
 <ul>
  <li>
   Strong skills in
   <strong>
    technical analysis, requirement breakdown, and test documentation
   </strong>
  </li>
 </ul>
 <p>
  <br/>
 </p>
 <ul>
  <li>
   Strong verbal and written communication skills
  </li>
  <li>
   Highly motivated to work with
   <strong>
    digital technologies
   </strong>
   and
   <strong>
    learnd new tools
   </strong>
  </li>
  <li>
   Excellent verbal and written
   <strong>
    English and Turkish
   </strong>
   communication skills
  </li>
  <li>
   Motivated, proactive, structured thinker with strong analytical and problem‑solving skills
  </li>
 </ul>
 <p>
  <br/>
 </p>
 <p>
  Nice to Have / Pluses
 </p>
 <p>
  <br/>
 </p>
 <ul>
  <li>
   Experience on Azure DevOps
  </li>
  <li>
   ISTQB Certification
  </li>
  <li>
   Banking/Finance sector experience
  </li>
  <li>
   Awareness of AI-assisted test generation, prompt quality control, and validation of AI outputs
  </li>
 </ul>
 <p>
  <br/>
 </p>
 <p>
  If you think you may take charge of the following
  <strong>
   responsibilities
  </strong>
  ;
 </p>
 <p>
  <br/>
 </p>
 <ul>
  <li>
   Acting as a
   <strong>
    bridge
   </strong>
   between developers and product owners
  </li>
  <li>
   Preparing detailed
   <strong>
    technical analysis and requirement breakdown
   </strong>
   documents
  </li>
  <li>
   Designing and executing
   <strong>
    Feature Tests
   </strong>
   and
   <strong>
    System Integration Tests (SIT)
   </strong>
  </li>
  <li>
   Designing and maintaining
   <strong>
    regression test suites
   </strong>
  </li>
  <li>
   Developing, maintaining and executing
   <strong>
    automated mobile tests
   </strong>
   (Appium preferred)
  </li>
  <li>
   Performing
   <strong>
    API testing
   </strong>
   and
   <strong>
    backend validation
   </strong>
  </li>
  <li>
   Coordinating
   <strong>
    User Acceptance Tests (UAT)
   </strong>
   with product teams
  </li>
  <li>
   Creating and maintaining
   <strong>
    test cases, scenarios, and defect reports
   </strong>
  </li>
  <li>
   Ensuring
   <strong>
    test traceability
   </strong>
   from requirements to execution
  </li>
  <li>
   Following Agile/Scrum ceremonies and contributing to refinement processes
  </li>
 </ul>
 <p>
  <br/>
 </p>
 <p>
  What do we offer:
 </p>
 <p>
  <br/>
 </p>
 <p>
  At ING we want your work to fulfill you in every way, and that is why we take care of even the smallest detail. Check out what is waiting for you;
 </p>
 <p>
  <br/>
 </p>
 <p>
  <strong>
   You First Become Your True Self, Then an INGer:
  </strong>
 </p>
 <p>
  <br/>
 </p>
 <p>
  <strong>
   Flexible
  </strong>
  and
  <strong>
   hybrid working models
  </strong>
  , including remote options every third week of the month and during summer.
  <strong>
   14 days of welcome leave
  </strong>
  in your first year&mdash;don&rsquo;t wait to pursue your dreams!
 </p>
 <p>
  <strong>
   Continuous Growth and Development:
  </strong>
 </p>
 <ul>
  <li>
   Access to global and local learning opportunities through
   <strong>
    ING Academy,
   </strong>
   <strong>
    LearnUp
   </strong>
   , and certification programs with leading universities.
  </li>
  <li>
   Opportunities to contribute to innovative projects both locally and globally while advancing personally and professionally.
  </li>
  <li>
   Flexible career experiences await you through
   <strong>
    Short-Term Assignments (STA), Long-Term Assignments (LTA), Mini Career opportunities, Double Major (&Ccedil;ifte Kariyer), Turuncu Misafir,
   </strong>
   and
   <strong>
    Global STA/LTA programs
   </strong>
   , designed to enhance your skills and broaden your experience across different teams, departments, and international locations.
  </li>
  <li>
   When you step into a managerial role at ING, our exclusive
   <strong>
    RISE Leadership Program
   </strong>
   empowers you to lead with confidence. Centered around technology and people, RISE equips ING leaders with advanced skills and a strategic mindset to navigate and thrive in a dynamic environment.
  </li>
 </ul>
 <p>
  <strong>
   A Dynamic and Supportive Work Environment:
  </strong>
 </p>
 <ul>
  <li>
   An informal and collaborative culture where
   <strong>
    your ideas
   </strong>
   and
   <strong>
    innovations are valued.
   </strong>
  </li>
  <li>
   Social clubs, celebrations, and events to help you balance work and fun.
  </li>
 </ul>
 <p>
  <strong>
   We Care About You:
  </strong>
 </p>
 <ul>
  <li>
   Comprehensive health insurance for you and your loved ones.
  </li>
  <li>
   Private pension plans to help you achieve your future goals.
  </li>
  <li>
   On-site amenities like a gym, coffee shops, a hairdresser, and more to simplify your daily life.
  </li>
 </ul>
 <p>
  <br/>
 </p>
 <p>
  At ING, we&rsquo;re dedicated to helping you achieve your goals by embracing flexibility, growth, and innovation.
 </p>
 <p>
  <br/>
 </p>
 <p>
  For more information about our
  <strong>
   Orange Culture
  </strong>
  , click here now:
 </p>
 <p>
  <br/>
 </p>
 <p>
  <br/>
 </p>
 <p>
  <strong>
   <em>
    ***Candidates are expected not to share any sensitive personal data.
   </em>
  </strong>
 </p>
 <p>
 </p>
</div>


Technical Analysis Specialist

Codefirst Information Tech

<p>Java Software Developer (3+ Years Experience)</p><p><b>Location:</b> Hybrid / Remote<br/><b>Company:</b> CodeFirst</p><p>Position Overview</p><p>We are looking for a <b>Java Software Developer with at least 3 years of experience</b> to join our engineering team. The ideal candidate will have strong experience in <b>Spring Boot and microservices architecture</b>, and will contribute to the development of scalable, high-performance backend systems.</p><p>You will work with modern technologies, participate in system design discussions, and help build reliable software products used by enterprise clients.</p><p>Responsibilities</p><ul><li>Design, develop and maintain <b>Java-based backend applications</b></li><li>Develop and maintain <b>microservices using Spring Boot</b></li><li>Build scalable and maintainable RESTful APIs</li><li>Collaborate with frontend developers, DevOps engineers and product teams</li><li>Write clean, testable and maintainable code</li><li>Participate in <b>code reviews and architecture discussions</b></li><li>Troubleshoot and resolve performance or production issues</li><li>Contribute to continuous improvement of development processes</li></ul><p>Required Skills (Must Have)</p><ul><li><b>3+ years of professional experience in Java development</b></li><li>Strong experience with <b>Spring Boot</b></li><li>Experience developing <b>microservices architectures</b></li><li>Experience with <b>RESTful API development</b></li><li>Knowledge of <b>SQL databases</b> (MySQL / PostgreSQL or similar)</li><li>Experience with <b>Git version control</b></li><li>Understanding of <b>software design patterns and clean architecture</b></li><li>Experience with <b>Docker or container-based environments</b></li><li>Good problem-solving and analytical skills</li></ul><p>Nice to Have</p><ul><li>Experience with <b>Kubernetes</b></li><li>Experience with <b>message brokers</b> (Kafka, RabbitMQ, etc.)</li><li>Knowledge of <b>NoSQL databases</b> (MongoDB, Redis)</li><li>Experience with <b>CI/CD pipelines</b></li><li>Experience working with <b>cloud platforms</b> (AWS, GCP, Azure)</li><li>Familiarity with <b>event-driven architectures</b></li></ul><p>Qualifications</p><ul><li>Bachelor's degree in <b>Computer Engineering, Software Engineering, or related fields</b></li><li>Strong communication skills</li><li>Ability to work in an <b>agile development environment</b></li></ul><p>What We Offer</p><ul><li>Opportunity to work on <b>challenging and scalable software projects</b></li><li>A collaborative and engineering-focused environment</li><li>Flexible working conditions</li><li>Continuous learning and professional development opportunities</li></ul><p>İş T&uuml;r&uuml;: Tam zamanlı</p><p>Maaş: 60.000,00TRY - 120.000,00TRY aylık</p>

Software Developer

Sezzle

<div><p><b>The salary range for this role is negotiable, the range being $6,000-$12,500 per month (Gross in USD), based on location and experience level.
</b></p><p><b>About Sezzle:</b></p>
<p>
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!</p>
<p><b>
Compensation</b>:</p>
<p>
For this principal development role, with 12+ years of experience, the compensation range is<b> $6,000 - $12,500 USD based on location and experience level </b>per month and in gross amount. This range acknowledges the extensive expertise, leadership capabilities, and significant contributions expected at this level, offering a competitive salary to reflect the value of advanced skills and experience</p>
<p><b>
About the Role:</b></p>
<p>
We are seeking a talented and motivated, best-in-class Principal Engineer for our Data Infrastructure. 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.</p>
<p>
Sezzle is growing; our data generation and consumption is growing with us at an increasing scale. Data is extremely valuable, and we want to empower the business, the engineers, and the rest of the organization to be able to read, write, and analyze large volumes of it quickly and efficiently.</p>
<p>
Sezzle is a heavy consumer of MySQL, Postgres, and Redshift, leveraging AWS tooling with Aurora RDS and DMS. We use DBT-based transformations and similar toolkits to populate a rapidly growing data lake that supports multiple data warehouses. It's scaled well with us so far, and we're looking to continue improving it, but we also want to step into new tooling and technologies.<br>
<br>
<b>What you'll do:</b></p>
<ul>
<li>End to end ownership of our database and data warehousing infrastructure, its KPIs and its SLAs, including MySQL, Postgres, CDC capture, and Redshift.</li>
<li>Lead optimizations in database and query performance.</li>
<li>Build and maintain tooling to help manage and upgrade our data infrastructure, continually improving with migrations and optimizations.</li>
<li>Partner with Development to ensure we ship solid queries against a battle-tested schema to meet the needs of our products and business.</li>
</ul><ul><li>Help Sezzle evolve our data systems beyond the current scale and stack with whatever tooling is necessary to handle processing high volumes of writes and events while performing complex ETL.</li>
<li>Evaluate and integrate new technologies, guiding the evolution of Sezzle's data infrastructure.</li>
<li>Help data engineers and analysts optimize Redshift and warehouse performance, including query tuning, modeling improvements, and cost management.</li>
</ul>
<p><b>What We look for:</b></p>
<ul>
<li><b>12+ years of experience</b> in DBA, SRE, or Data Engineering roles, with a strong track record of scaling production-grade systems.</li>
<li>Deep expertise with <b>MySQL, Postgres, AWS Redshift or similar products</b>, including performance tuning, table design, and workload management.</li>
<li>Advanced proficiency in <b>SQL.</b></li>
<li>Strong hands-on experience with data replication and ETL/ELT frameworks, especially <b>DBT</b>, <b>AWS DMS</b>, or similar tools.</li>
<li>Strong understanding of <b>data modeling</b>, distributed systems, and warehouse/lake design patterns.</li>
<li>Ability to work in a fast-paced, collaborative environment with excellent communication and documentation skills.</li>
</ul>
<p><b>Preferred Knowledge and Skills:</b></p>
<ul>
<li>Prior experience in <b>high-growth, data-intensive fintech</b> or similar regulated environments.</li>
<li>Knowledge of <b>lakehouse architectures</b> and modern stacks such as Snowflake, Databricks, Iceberg, or Delta Lake.</li>
<li>Some background in designing <b>scalable, fault-tolerant data pipelines</b> using modern orchestration tools (Airflow, Dagster, Prefect, etc.) processing anywhere from 100GB to 1 TB of new data a day</li>
<li>Familiarity with <b>streaming technologies</b> (Kafka, Kinesis, Flink, Spark Streaming).</li>
<li>High enthusiasm for using AI to be as productive as possible.</li>
</ul>
<p><b>About You:</b></p>
<ul>
<li><b>You have relentlessly high standards</b> - 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><b>You're not bound by convention</b> - your success&mdash;and much of the fun&mdash;lies in developing new ways to do things</li>
<li><b>You need action</b> - speed matters in business. Many decisions and actions are reversible and do not need extensive study. We value calculated risk-taking.</li>
<li><b>You earn trust</b> - you listen attentively, speak candidly, and treat others respectfully.</li>
<li><b>You have backbone; disagree, then commit </b>- 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>
<li><b>You deliver results </b>- you focus on the key inputs and deliver them with the right quality and in a timely fashion. Despite setbacks, you rise to the occasion and never settle.</li>
</ul>
<p><b>Sezzle's Technology Stack:</b></p>
<ul>
<li><b>Languages: </b>Golang, Typescript, Python</li>
<li><b>Frontend: </b>Typescript - React and React Native</li>
<li><b>Backend: </b>Golang</li>
<li><b>Database: </b>MySQL, Postgres, Elasticsearch</li>
<li><b>DevOps &amp; Cloud: </b>AWS, Kubernetes</li>
<li><b>Version Control: </b>Git</li>
<li><b>CI/CD: </b>Gitlab</li>
<li><b>Testing: </b>Developer and AI-driven, focus on automated end-to-end, integration, and unit tests</li>
<li><b>Open Source:</b> Sezzle is focused on using open source, and we build what we can before buying!</li>
</ul>
<p><b>What Makes Working at Sezzle Awesome?</b></p>
<p>
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.</p>
<p>
#Li-remote #full-time</p></div>

Principal Engineer - Data Infrastructure

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