Fintech Backend Engineer: Scalable APIs & Identity Security

Ajaib; United States; Remote; USD 140,000 - 210,000; Full time

Benefits offered by this job

Performance bonus

Comprehensive private health insurance

Paid time off

Company-sponsored training, courses, &

Career growth opportunities

Employee discounts, partnerships, &amp

Job summary

Ajaib Group is a fast-growing Indonesian fintech transforming retail finance and expanding access to financial services. We seek a senior backend engineer to design, build, and operate scalable services used across product teams, owning major components end-to-end with monitoring, on-call support, and clear API contracts.

You will lead authentication/authorization work, improve observability, and scale Kafka-based messaging and API gateways, collaborating with Security, Infra, and Architecture

Qualifications

• Bachelor's degree in CS or equivalent practical experience.
• 5+ years of backend engineering with ownership of production services.
• Strong skills in Java, Go or other modern backend language.
• Knowledge of microservices, REST/gRPC, event-driven design.
• Experience with relational and NoSQL databases, Redis, Kafka.
• Auth tech: OAuth2, OpenID Connect, JWT, secure coding.
• Cloud: GCP or AWS, containers, CI/CD.

Responsibilities

• Design, build, and operate scalable backend services and APIs used by multiple product teams.
• Own large services end to end with monitoring, alerts, and on-call support.
• Design stable APIs with contracts, versioning, and safe deprecation.
• Improve identity and access features including sign-in, sessions, tokens, and permissions.
• Increase resilience with rate limiting, graceful degradation, and safe rollouts.
• Improve observability with metrics, logs, traces, and SLIs with dependent teams.
• Lead design reviews and conduct code reviews.
• Investigate incidents, perform root cause analysis, and deliver fixes.
• Mentor mid-level engineers and share knowledge.
• Work with Security, Infra, Architecture to deliver reliable solutions.
• Scale Kafka and messaging platforms for organization-wide workflows.
• Build high-throughput, low-latency API Gateways and WebSocket infra.
• Develop feature flagging for safe deployments and canary testing.

Skills

Backend engineering

Java

Go

Microservices

REST/gRPC APIs

Observability

Kafka

Authentication/Authorization

OAuth2

OpenID Connect

JWT

GCP/AWS

CI/CD

Databases (SQL/NoSQL)

Redis

Education

Bachelor's degree in Computer Science or equivalent

Tools

Kafka

Redis

Job description

Ajaib Group is a fast-growing Indonesian fintech transforming retail finance and expanding access to financial services. We seek a senior backend engineer to design, build, and operate scalable services used across product teams, owning major components end-to-end with monitoring, on-call support, and clear API contracts.

You will lead authentication/authorization work, improve observability, and scale Kafka-based messaging and API gateways, collaborating with Security, Infra, and Architecture