Backend Engineer

Build the systems behind everyday commerce.

At Qashier, we’re building the operating system for SMEs across Southeast Asia—bringing POS, payments, and financial services into one platform.

For the merchants who depend on us, backend reliability has an immediate impact: a completed payment, a smooth checkout, a business that keeps moving.

We’re looking for a Backend Engineer with strong technical judgment and a builder’s mindset. You’ll take problems from design through production, make decisions that shape our architecture, and own how your services perform in the real world.

What you’ll own

• Core backend services. Design, build, and operate the APIs and services powering our POS and payments platform, supporting high-volume, real-time transactions.
• Transaction correctness. Build systems that handle retries, duplicate requests, concurrency, and partial failures without compromising data integrity.
• Architecture and technical decisions. Define service boundaries, evaluate technologies, and make thoughtful trade-offs across performance, reliability, complexity, and cost.
• Performance and scale. Identify bottlenecks, improve database access patterns, and optimise latency and throughput as transaction volumes grow.
• Production reliability. Build useful monitoring and alerting, investigate incidents, and turn root cause analysis into durable improvements.
• Engineering quality. Write maintainable code, build meaningful unit, integration, and performance tests, and strengthen delivery through code reviews and CI/CD.
• Delivery from problem to outcome. Work closely with product managers, designers, and engineers to clarify requirements, challenge assumptions, and ship solutions that work for merchants

Experience that would stand out

• Payments, fintech, POS, or other transaction-intensive platforms.
• Event-driven systems, message queues, or streaming infrastructure.
• Measurable improvements to production reliability, latency, throughput, or infrastructure cost.
• Experience evolving an existing system while keeping it running reliably.

Why this role matters

You’ll work on systems directly connected to merchants’ revenue and daily operations. Your contribution will extend beyond feature delivery to the architecture, reliability, and engineering practices that support Qashier’s growth across Southeast Asia.

If you enjoy difficult backend problems and taking responsibility for what you build, we’d like to meet you.

Apply now, email [email protected], or book a conversation with Micah.

Learn more at qashier.com.

Requirements

Responsibilities

Service ownership

• Design, build and operate core backend APIs and services that power our POS and payments flows with a focus on correctness and uptime.
• Own the end-to-end lifecycle for the services you build, from design and testing through deployment and live support.
• Maintain clean, testable code and CI/CD pipelines so releases are predictable and reversible when needed.

Reliability and scale

• Implement patterns for retries, idempotency, concurrency control, and partial-failure handling to protect transaction integrity.
• Profile and optimise database access, caching, and throughput to reduce latency as traffic grows.
• Build monitoring, alerting, and runbook-driven incident response to minimise merchant impact.

Delivery and collaboration

• Work closely with product, design, and other engineers to clarify requirements and translate them into robust technical solutions.
• Drive architectural trade-offs that balance performance, reliability, complexity, and cost for the platform.
• Participate actively in code reviews and post-incident analyses, and turn learnings into durable improvements.

Requirements

Qualifications & Experience

• 5+ years of backend engineering experience with systems you have built, deployed, and supported in production.
• Proven track record building scalable APIs and services for high-volume, real-time applications.
• Experience maintaining and evolving existing systems while keeping them reliably running in production.

Hard Skills & Knowledge

• Strong proficiency in Node.js, Go, or Python, supported by solid software design and problem-solving fundamentals.
• Deep understanding of distributed systems concepts including concurrency, asynchronous processing, retries, idempotency, and failure modes.
• Solid database expertise with relational and/or NoSQL systems, including data modelling, indexing, query optimisation, and consistency trade-offs.
• Hands-on experience with microservices and cloud platforms such as GCP, AWS, or Azure, plus familiarity with queues or streaming systems.
• Practical testing and delivery skills: unit, integration, and performance testing, automated CI/CD, and disciplined code review practices.

Soft Skills & Qualities

• Ability to diagnose and resolve production issues using monitoring, logging, and root cause analysis, and to convert fixes into long-term solutions.
• Clear engineering judgment with the ability to explain architectural decisions and trade-offs to technical and non-technical partners.
• Strong ownership and communication: you clarify ambiguous requirements, coordinate across functions, and follow through after deployment.
• Preferred experience in payments, fintech, POS, or other transaction-intensive platforms, and with event-driven architectures or message queues.

Skills

Node.js (Javascript Library), JavaScript (Programming Language), Next.js (Javascript Library)