Senior Python Backend Engineer (Payment Systems/Payment Gateways)
Location:
Onsite District 2
Interview Process:
1 rounds
Rate:
35-40M
Open Headcount:
1
About the Role
We are looking for a highly skilled
Senior Python Backend Engineer
with strong experience in
building and optimizing payment systems
. You will be responsible for designing, developing, and maintaining scalable backend services, focusing on
transaction integrity, payment integrations, and high availability
.
You will work independently while collaborating closely with cross-functional teams on
API architecture, data consistency, background processing, and observability setup
.
Key Responsibilities
Design, develop, and optimize
complex API services
(idempotency, retries, webhooks).
Build and maintain
transactional flows
on PostgreSQL ensuring ACID compliance.
Design and optimize
database schemas
, indexes, and constraints.
Implement
background jobs
(reconciliation, retry queues) and asynchronous workflows.
Establish
observability practices
: metrics, logging, and distributed tracing.
Own and maintain
payment modules
, admin console, and gateway integrations.
Troubleshoot system performance, scalability, and reliability issues.
Contribute to
solution architecture
and
mentor junior developers
.
Mandatory Requirements
Proficiency in Python
with strong hands-on experience using
FastAPI
(or similar frameworks).
Proven experience working on
payment systems
in production (at least one live project).
Familiarity with
payment gateways
(Stripe, Adyen, PayPal, local PSPs) and
PCI compliance basics
.
Strong knowledge of
distributed systems
,
concurrency
, and
transactional integrity
.
Deep understanding of
PostgreSQL
(schemas, indexes, constraints, JSONB).
Knowledge of
idempotency
,
deduplication
,
webhooks
, and
security best practices
(TLS, JWT).
Experience implementing
asynchronous tasks
using
Celery
,
RQ
, or
asyncio background tasks
.
Preferred Qualifications
Experience designing APIs at scale (API gateway, rate limiting, multi-tenant architectures).
Hands-on experience with
Redis
,
Kafka/RabbitMQ
, or
MongoDB (motor)
.
Working knowledge of
Kubernetes
(deployments, services, ConfigMap, Secrets).
Why Join Us
Work on
cutting-edge payment and fintech systems
with high scalability.
Flexible working hours.
Long-term engagement
with growth and leadership opportunities.
Competitive compensation and performance-based rewards.
How to Apply
Please send your updated
CV (in English)
to
justindoan.work@gmail.com
with the subject line:
Application – Senior Python Developer.