# Senior Backend Engineer (Go) at Kastcard

> Remote · Brazil · Senior · Backend · open. Source: https://alderhq.app/jobs/pinpoint%3Akastcard%3A558454 (read 2026-11-05).

## Facts (observed)

- Company: [Kastcard](https://alderhq.app/companies/kastcard)
- Location text: São Paulo, São Paulo
- Where it can be done from (inferred): Remote · Brazil (evidence: "Location: São Paulo, São Paulo")
- Posted: already open when tracking began; date unknown
- First seen by alder: 2026-11-04 · last verified: 2026-11-04
- Reposted: 0 times · edited: 0 times
- Apply on the employer's site: https://careers.kast.xyz/en/postings/a99c46f3-f354-472b-be55-c81e61a18ac1
- Skills listed (inferred): Go, Ruby/Rails, PostgreSQL, Redis, Kafka, AWS, Kubernetes, Docker, Terraform, Distributed systems

## Pay and sponsorship

- Posted pay: not posted

## Description (the employer's text)

We're looking for a hands-on Senior Backend Engineer to help build and scale KAST's LATAM domestic payment rails.

You'll be a core contributor on the effort to onboard additional fiat payment providers as redundant, hot-swappable rails. You'll work closely with Product, Compliance/Risk, L3 production support, and provider partners to ship reliable, auditable payment systems that meet the LATAM Central Banks’ requirements.

Location: remote from Brazil.

### Responsibilities

- Design and build production-grade backend microservices and APIs in Go
- Implement resilient fallback and routing logic across providers (limits, uptime, KYC eligibility) with feature-flagged rollout and safe rollback paths
- Partner with the fraud detection flow and onboarding/KYC integration to keep transaction and onboarding flows compliant and observable
- Contribute to FSDs, technical design docs, and delivery estimates; break down work into forward-compatible increments and track open dependencies/pendencies
- Design reliable, auditable, and secure systems with strong observability and operational workflows
- Help raise the bar on backend engineering standards through code review, technical guidance, and mentorship of squad members
### Skills

- 5+ years of software engineering experience
- Strong backend engineering expertise, particularly with Go
- Experience building production-grade APIs and distributed systems, including event-driven / webhook-based integrations with third-party providers
- Solid understanding of system reliability, security, and auditability, especially for money-movement or transactional systems
- Ability to work through ambiguity: reverse-engineer existing flows, freeze interfaces early, and design for parallel delivery when dependencies aren't fully built yet
- Comfortable working cross-functionally with product, compliance, operations, and external provider/partner teams
- Startup mindset with strong ownership and execution ability
- Experience with cloud infrastructure and modern engineering workflows (AWS, containers, relational databases, streaming/messaging)
### Benefits

- Experience integrating payment providers / payment rails and reasoning about redundancy, provider failover, and reconciliation
- Familiarity with PIX and the Brazilian payments landscape, including Central Bank regulatory requirements and named virtual accounts
- Experience with KYC/KYB, AML, transaction monitoring, sanctions screening, or fraud/risk tooling
- Experience in crypto, stablecoins, or Web3 infrastructure (e.g. BRL ↔ USDC / stablecoin conversion flows)
- Experience decoupling tightly-coupled systems into provider-agnostic, adapter-based architectures
- Spanish language skills to coordinate with local providers
- Experience with AWS (ECS Fargate, Aurora/PostgreSQL), Kafka, Redis, Kubernetes, or Terraform

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Data: alder (https://alderhq.app). Cite https://alderhq.app/jobs/pinpoint%3Akastcard%3A558454 and the date you read it. Observed facts come from the employer's own listing; location reach, level, family and skills are inferences.