Senior Software Engineer

Company: Fraud Deflect

Language Requirement: Native/fluent English (client‑facing). ALL RESUMES MUST BE SENT IN ENGLISH.

Fraud Deflect aims to revolutionize Friendly Fraud and Chargeback Management by bringing Integrity, Trust, and Transparency to an industry often clouded in secrecy. We strive to eliminate unethical practices and provide a clear pathway for our clients.

We are seeking an experienced Senior Software Engineer to lead key technical projects, mentor developers, and collaborate directly with clients. You will design and scale our API‑first platform in Python, automate end‑to‑end operational workflows, build reliable data/ETL pipelines, and ship secure services — powering flows, dispute/chargeback handling, and analytics.

• Lead & mentor: Guide junior and mid‑level engineers through design reviews, pairing, and actionable feedback. Work with leadership to align tech to expectations. Collaborate with teams across the organization.
• Architect & build APIs (API‑first): Design, document, and operate RESTful services with clear models, versioning/deprecation, idempotency keys, pagination, consistent error taxonomies, and SLAs. Implement authentication/authorization (OAuth2/OIDC), API keys, mTLS where appropriate, rate limiting, and schema/contract governance. Publish dev‑friendly docs, examples, Postman collections, and lightweight SDKs.
• Payments & chargebacks: Integrate with gateways/acquirers and network APIs; model the disputes lifecycle. Build reporting with strong auditing.
• Device intelligence & fraud defenses: Design and integrate device fingerprinting and bot‑mitigation strategies with privacy‑respecting controls and consent. Feed signals into risk scoring, enforce step‑up challenges, and close the loop via feedback from chargeback outcomes to continuously reduce false positives.
• Process automation: Automate repetitive, error‑prone steps across disputes and ops: evidence packet assembly, data collection from internal/external systems, reconciliation runs, SLA timers/notifications, and compliance checks. Use workflow orchestration and event‑driven patterns to implement retries, compensations, and human‑in‑the‑loop approvals.
• Python services at scale: Build robust backends using modern Python (typing, OOP, asyncio/multiprocessing, free-threading), performance profiling/tuning, and safe concurrency patterns.
• Data & ETL/ELT pipelines: Design, operate, and optimize high‑volume pipelines (batch/streaming) with validation, retries, backpressure, partitioning, incremental loads, and data contracts.
• Storage & modeling: Use SQLAlchemy with relational databases (MySQL/PostgreSQL/etc.). Work with ClickHouse; apply lake/lakehouse patterns (S3 + Parquet) for analytics at scale.
• Cloud & platform: Build, deploy, and operate services on AWS (e.g., EKS/ECS, Lambda, S3, RDS, Redshift, Kinesis/SNS/SQS, API Gateway/IAM). Containerize with Docker and orchestrate with Kubernetes.
• Quality & reliability: Own CI/CD (e.g., GitHub Actions); implement unit/integration/contract tests; enable observability with structured logs, metrics, and traces; support canary/blue‑green deploys and runbooks.
• Security & compliance: Apply secure coding, secret management, least‑privilege IAM, and auditable changes; design with PCI DSS considerations.
• Client collaboration: Meet with clients to gather requirements, present designs, explain trade‑offs, and provide technical guidance in clear, native/fluent English.
• Access control: Implement multi‑level user/role management (RBAC/ABAC) and end‑to‑end auditability.

• English: Native/fluent; comfortable leading client calls, workshops, and written communication. Resumes must be submitted in English.
• Python expertise: Advanced proficiency with modern Python (3.x; 3.12+ preferred), OOP/design patterns, typing/mypy, async I/O and multiprocessing, performance profiling, packaging, and testing.
• API engineering: Proven experience designing, building, documenting, and operating RESTful APIs at scale (versioning, pagination, idempotency, security best practices, webhooks).
• Fintech domain: Hands‑on with payments processing, chargebacks/disputes, reconciliation/settlement, and payment network/vendor integrations.
• Device fingerprinting & bot detection: Practical experience integrating device intelligence and behavioral analytics for risk decisions, with privacy/regulatory awareness.
• Automation & workflows: Track record automating operational processes using orchestration/workflow tools and event‑driven systems; human‑in‑the‑loop patterns where needed.
• Data platforms: Strong SQL with SQLAlchemy; production experience with MySQL/PostgreSQL and ClickHouse or similar columnar engines; familiarity with data lake/lakehouse architectures.
• Pipelines: Building ETL/ELT with Airflow/Prefect/Dagster; understanding batch vs. streaming, data contracts, and schema evolution.
• Cloud & DevOps: AWS proficiency; Docker/Kubernetes; CI/CD with GitHub Actions (or similar); solid observability practices (logs/metrics/traces).
• Breadth of languages: Comfort beyond Python with both high‑level and low‑level languages, e.g., two or more among Go, Rust, Java, C/C++.
• Systems fundamentals: Networking/HTTP/TLS, concurrency, memory/CPU profiling, filesystems, and distributed systems basics.

• Risk/fraud systems (rules, features, model serving), KYC/AML, and compliance (PCI DSS, SOC 2).
• Messaging/streams: Kafka, Kinesis, SQS/SNS; patterns like outbox, sagas/compensations.
• Infrastructure as Code (Terraform or CloudFormation).
• Data quality tooling (e.g., Great Expectations) and governance practices.
• Workflow engines for long‑running, durable business processes.
• Python web frameworks experience (e.g., FastAPI, Django/DRF, Flask).
• Deep exposure to popular product management software.
  

• Send your resume in English and (optionally) links to relevant APIs, docs, or code samples that showcase your Python, device fingerprinting, automation, and payments/chargebacks work. ALL RESUMES MUST BE SENT IN ENGLISH.