backend / distributed systems

Iman Ahrari

Senior Backend Engineer

Since 2021, building the parts of fintech and logistics platforms that aren't allowed to go down: payment integrations, identity systems, async pipelines, and the dashboards that watch all of it. Open to relocation across the UK, Europe, Turkey, and Oman.

iahrari.github.io / github.com/iahrari / linkedin.com/in/iahrari / i.ahrari@pm.me

impact, measured

A few numbers from the logs

Feature delivery speed
with AI-assisted workflows

40%

Cold-start latency cut
migrating Lambdas to Spring Boot

55%

Ticket resolution time
via Camunda BPMN automation

35%

Slow-query latency cut
via Postgres index tuning

45%

Data consistency
across millions of subsidy calcs

100%

deployment history

Experience

May 2024 — present
current

Senior Backend Engineer

Kixy — UK fintech platform, remote / London

Orchestrated agentic AI workflows — used AI coding agents (Claude Code and others) for architecture, code generation, and test automation, cutting full-stack delivery time by 40%.
Modernised legacy Lambdas — migrated JavaScript AWS Lambda functions into structured Spring Boot microservices, dropping cold-start latency by up to 55%.
Rebuilt identity from scratch — replaced AWS Cognito with a custom Spring Security OAuth2.0 framework, adding SSO and fine-grained role management.
Owned payment integrations — Railsr, ClearBank, Plaid, Bank of Asia, and Pay.UK CoP, secured with fine-grained IAM, DynamoDB, and SQS policies.

Java · Spring Boot · Spring Security · AWS (EKS, Lambda, SQS, IAM, DynamoDB, Cognito) · Plaid API · Redis · Grafana · Prometheus · Kibana APM · Kafka · PostgreSQL · Debezium · Kubernetes · GitHub Actions · Jira · MariaDB · Flagsmith

Mar 2022 — May 2024

Software Engineer

Snappbox — logistics & ridesharing platform, Tehran

Automated support routing with Camunda BPMN/DMN engines, cutting average ticket resolution by 35%.
Built a high-scale batch pipeline on RabbitMQ and Redis, processing millions of driver subsidy calculations at 100% data consistency.
Migrated live systems to Keycloak SSO, tightening session sharing and reducing unauthorized access attempts.
Tuned Postgres under Camunda's workload, cutting slow-query latency by 45%.

Java · Spring Boot · Spring Gateway · Spring Flux · Camunda BPMN/DMN · Keycloak · Redis · RabbitMQ · Docker · Kubernetes · GitHub Actions · Prometheus · Grafana · Kafka · NATS · MongoDB · Jira · Jenkins

Nov 2021 — Mar 2022

Trainee / Junior Software Engineer

Snappbox — Tehran

Built backend APIs and database operations in high-throughput Spring-based microservices, cutting support-queue bugs by 20%.
Wrote JUnit and Mockito integration test suites, lifting coverage to 85% across core logistics paths.

Java · Spring Boot · JUnit · Mockito · Git · Maven · MariaDB

dependencies

Stack

Languages

Java (up to 25)GoJavaScriptSQLKotlin

Frameworks & tools

Spring BootSpring SecurityHibernate / JPACamunda BPMN/DMNKeycloakMaven

Databases & messaging

PostgreSQLRedisRabbitMQApache KafkaDynamoDBMongoDBMariaDBFlagsmith

Cloud & observability

AWS EKSLambdaSQSCognitoSecrets ManagerIAMDockerKubernetesGitHub ActionsGrafanaPrometheusKibana APMLog4j

provenance

Education

University of Birjand

B.Eng., Computer Engineering

Oct 2018 — Mar 2023