CleanCode Agency

We're hiring a Java developer to build ultra-low-latency systems using Aeron and Chronicle.

You will design and optimize high-throughput messaging with Aeron (IPC/UDP, Cluster, Archive), build persistent off-heap data layers with Chronicle Queue and Chronicle Map, and tune JVM performance down to the microsecond.

You bring strong Java (17+), production experience with Aeron or Chronicle Wire & Queue, understanding of mechanical sympathy, lock-free concurrency, off-heap memory, and Linux perf tooling. Trading or market data background preferred.

Bonus: SBE/zero-copy serialization, LMAX Disruptor, kernel bypass (OpenOnload/DPDK), event sourcing, single-writer architectures.

Competitive pay. Hard problems. Microseconds matter.

We're looking for a UI/UX Designer to own the end-to-end experience across our web and mobile platforms. You'll shape how people list, discover, negotiate, and transact — making every interaction feel fast, safe, and satisfying. You'll work closely with product managers, engineers, and our data team to turn user insights into intuitive interfaces.

What You'll Do

• Design user flows, wireframes, and high-fidelity prototypes for listing creation, search and discovery, messaging, checkout, and seller dashboards.
• Conduct user research - interviews, usability tests, and survey analysis - to deeply understand the motivations and pain points of both buyers and sellers.
• Build and maintain a scalable design system that ensures visual consistency across platforms and supports rapid iteration.
• Collaborate with engineers to ensure designs are implemented with precision, providing specs, assets, and guidance through development.
• Use data (conversion funnels, heatmaps, session recordings) to identify friction points and validate design decisions through A/B testing.
• Design trust and safety experiences - rating and review flows, identity verification prompts, dispute resolution interfaces- that make users feel confident transacting with strangers.
• Champion accessibility standards (WCAG 2.1 AA) and inclusive design principles across the product.

What We're Looking For

• 2+ years of product design experience, ideally in a marketplace, e-commerce, or consumer app environment.
• A strong portfolio demonstrating end-to-end product thinking - not just polished visuals, but evidence of problem framing, iteration, and measurable outcomes.
• Proficiency in Figma (components, auto-layout, prototyping) and familiarity with handoff and collaboration tools.
• Experience designing for both iOS and Android, with a solid grasp of platform conventions.
• Comfort with qualitative and quantitative research methods - you can run a usability test and also interpret a funnel chart.
• Strong communication skills - you can articulate design rationale to stakeholders and incorporate feedback without losing sight of the user.

Bonus Points

• Experience with circular economy, sustainability, or peer-to-peer platforms.
• Familiarity with motion design or micro-interactions (Lottie, Rive, or similar).
• Background in illustration or brand design.
• You've designed complex trust, safety, or payment flows before.

What We Offer

• Competitive salary and equity participation.
• Flexible, remote-first work culture with optional co-working stipend.
• Annual learning budget for courses, conferences, and tools.
• A mission-driven team that genuinely cares about reducing waste and making reuse easy.
• The opportunity to shape a product used by millions of people every day.

We're looking for an experienced Go Engineer to join our team and help build, scale, and maintain our payment gateway platform. You'll work on high-throughput, low-latency systems that process financial transactions in real time, ensuring reliability, security, and compliance at every layer.

What You'll Do

Design, develop, and maintain core payment processing services in Go. Build and optimize APIs for merchant integration, transaction routing, and settlement workflows. Implement secure communication with card networks, acquiring banks, and alternative payment providers.

 Ensure PCI DSS compliance across services and infrastructure. Improve system observability through structured logging, metrics, and distributed tracing. 

Participate in architecture decisions, code reviews, and incident response. 

Collaborate with product, risk, and compliance teams to ship features that meet regulatory requirements.

What We're Looking For

3+ years of professional experience writing production Go. Strong understanding of concurrency patterns (goroutines, channels, context propagation). 

Experience building and operating microservices in a distributed environment. 

Familiarity with payment industry concepts such as authorization, capture, refunds, chargebacks, and tokenization. 

Solid grasp of relational databases (PostgreSQL preferred) and transactional integrity. 

Experience with message brokers (Kafka, RabbitMQ, or NATS). 

Comfort working with Docker, Kubernetes, and CI/CD pipelines. Understanding of security best practices: encryption at rest and in transit, secret management, and secure coding.

Nice to Have

Prior experience in fintech, payments, or banking. Familiarity with PCI DSS, PSD2, or 3D Secure protocols.

 Experience with gRPC and Protocol Buffers. 

Knowledge of event-driven architectures and CQRS/event sourcing. Contributions to open-source Go projects.

Tech Stack

Go, PostgreSQL, Redis, Kafka, gRPC, Kubernetes, Prometheus, Grafana, Terraform.

What We Offer

Competitive salary and equity participation.

 Flexible remote or hybrid work arrangement.

 Budget for conferences, courses, and certifications. 

Modern engineering culture with a focus on ownership, autonomy, and continuous improvement. 

The opportunity to work on systems that move real money at scale.