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Diego Reyes

Backend engineer · Payment infrastructure · Berlin

Diego Reyes

Three years building high-throughput payment infrastructure in Go and Kafka — including a 40% cut in payment processing latency at Stripe.

  • 3years in backend engineering
  • 40%lower payment processing latency
  • 99.7%of duplicate-charge incidents eliminated
  • 9 minMTTR on payment alerts, down from 28

Case study

Taking the waiting out of payment events

How he redesigned Stripe's payment event fan-out service to cut end-to-end latency.

Stripe · Backend Software Engineer · Go · Apache Kafka

Redesigning the payment event fan-out service

Problem

The payment event fan-out service relied on synchronous HTTP calls.

Approach

Redesigned the service in Go, replacing the synchronous HTTP calls with Kafka-based async messaging.

Outcome

End-to-end processing latency reduced by 40%.

Services & infrastructure

Reliability, observability and throughput

Payment and payroll systems built at Stripe in Berlin and Buk in Santiago.

Stripe · Charge reconciliation

Idempotent retry logic

Built idempotent retry logic for charge reconciliation, covering three merchant tiers.

99.7% of duplicate-charge incidents eliminated

Stripe · OpenTelemetry

Payment service observability

Structured traces, metrics and logs added to the payment services via OpenTelemetry.

MTTR on payment service alerts from 28 min to 9 min

Stripe · Go

Internal Go service template

Contributed to a service template that standardises health-check and graceful shutdown patterns.

Adopted by 6 other backend teams

Buk · Go · PostgreSQL

Payroll calculation APIs

REST APIs for a payroll calculation engine, written in Go with PostgreSQL.

Serving 1,200 Chilean SME clients

Buk · Event-driven workers

Batch payroll migration

Legacy batch payroll jobs migrated to event-driven workers.

Monthly processing from 6 hours to 35 minutes

Buk · Testing

Integration and contract tests

Integration and contract tests written over 8 months.

Service coverage raised from 54% to 88%

Tech stack

What he builds with

  • Go
  • PostgreSQL
  • Apache Kafka
  • Docker
  • Kubernetes
  • gRPC
  • Redis
  • GitHub Actions
  • Datadog
  • AWS
  • OpenTelemetry

A backend engineer specialising in distributed systems and event-driven architecture, with a strong focus on reliability, observability and clean API design.

Diego is a Backend Software Engineer at Stripe in Berlin, working on high-throughput payment infrastructure in Go and Kafka. Before that he was a Junior Backend Developer at Buk in Santiago, building payroll APIs and event-driven workers, and interned at Cornershop (Uber).

At Buk he was part of the on-call rotation and resolved 12 production incidents, each with a documented postmortem.

  • Based inBerlin, Germany
  • CurrentlyStripe
  • FocusDistributed systems, event-driven architecture
  • DomainsPayments, payroll
  • EducationBSc Computer Science, Universidad de Chile

Experience

From Santiago to Berlin

  1. Aug 2023 — Present

    Backend Software Engineer

    Stripe, Berlin

    Payment event fan-out redesign (40% lower latency), idempotent charge-reconciliation retries, OpenTelemetry observability and the internal Go service template.

  2. Mar 2022 — Jul 2023

    Junior Backend Developer

    Buk, Santiago

    Payroll calculation APIs for 1,200 SME clients, event-driven payroll workers, test coverage from 54% to 88%; on-call with 12 incidents resolved.

  3. Jan 2022 — Feb 2022

    Software Engineering Intern

    Cornershop (Uber), Santiago

    Built a data pipeline aggregating delivery-time metrics from Kafka topics into a PostgreSQL reporting schema; shipped two bug fixes to the order-status microservice, both merged and deployed.

Education & certifications

Training and open source

  • BSc Computer Science, Universidad de Chile — GPA 6.4 / 7.0, top 12% of cohortMar 2018 – Dec 2021
  • AWS Certified Developer – Associate2023
  • Go concurrency workshop, GopherCon Europe2024
  • Open-source contributor to go-migrate2 merged PRs

Contact

Scaling a payment system?

diego.reyes@email.com

  • +49 160 900 3341
  • Berlin, Germany
  • linkedin.com/in/diegoreyes
  • github.com/diegoreyes-dev

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