Senior Software Engineer

HolistiTech; Johannesburg; Hybrid; ZAR 600,000 - 900,000; Full time

Job summary

A boutique consultancy in Johannesburg seeks a Senior Software Engineer to lead the design and implementation of high-performance systems for capital-markets clients. The ideal candidate will have strong coding skills in Python and Java, along with experience in financial services. This is a hybrid/remote position offering an exciting opportunity to shape next-generation fintech solutions.

Qualifications

• 6+ years of professional software engineering experience, ideally in financial services.
• Prior exposure to capital-markets workflows is a strong plus.
• Deep understanding of JVM tuning and async programming.

Responsibilities

• Lead the design and implementation of high-performance systems.
• Build resilient back-end services using Python and Java.
• Own technical road maps and drive platform scalability.

Skills

Python coding

Java coding

Analytical problem-solving

DevOps practices

Mentorship

Education

Degree (NQF6+) in Computer Science, Engineering, Mathematics, or related field

Tools

PostgreSQL

Docker

Kafka

GitHub Actions

Job description

Senior Software Engineer

Location:Johannesburg, South Africa (Hybrid / Remote)

Level:Mid‑Senior

What You’ll Do

• Lead the design and implementation of high‑performance, distributed systems for capital‑markets clients.
• Build resilient back‑end services inPythonandJava(SpringBoot, FastAPI, Django).
• Work with quants, product owners, and fellow engineers to deliver low‑latency trading, risk, and analytics solutions.
• Own technical road‑maps, drive platform scalability, and mentor junior developers.

What Success Looks Like

CompetencyHow You’ll Show ItTechnical MasteryExpert coding in PythonandJava; deep understanding of JVM tuning, async Python, and micro‑services.Business AlignmentTranslate trading‑desk needs into secure, scalable code that delivers measurable latency or throughput gains.Analytical Problem‑SolvingDiagnose memory leaks, optimise SQL/streaming queries, and debug production incidents under pressure.Code Quality & DevOpsEnforce peer reviews, automated tests, Git workflows, and CI/CD pipelines.Leadership & MentorshipPair‑program, run brown‑bag sessions, and set engineering standards for a growing team.AdaptabilityRapidly learn unfamiliar asset classes, protocols, and toolchains.Results FocusShip features on schedule, with rock‑solid performance and user experience.

Minimum Qualifications

• 6+years of professional software‑engineering experience—ideally in financial‑services, trading, or other low‑latency environments.
• Degree (NQF6+) in Computer Science, Engineering, Mathematics, or related field.
• Prior exposure to capital‑markets workflows (trade capture, pricing, analytics) is a strong plus.

Technical Stack

AreaPrimary ToolsLanguagesPython3.x,Java11+(SpringBoot, Vert.x), BashFrameworksDjango, FastAPI, Flask • SpringBoot, SpringWebFluxAsync / Concurrencyasyncio, aiohttp • JavaCompletableFuture, ReactorData & PersistencePostgreSQL, MySQL, Redis • MongoDB • Kafka StreamsMessaging / StreamingApacheKafka, RabbitMQ, RedisStreams, FIX/WebSocketContainerisationDocker & Docker‑Compose • Kubernetes / HelmCI/CD & IaCGitHub Actions, Jenkins • Terraform, AnsibleTestingpytest, unittest, tox • JUnit5, TestcontainersObservabilityPrometheus, Grafana, Jaeger, Sentry, NewRelicSecurityOAuth2, JWT, TLS, OWASP, encryption best practicesIntegrationBloomberg, Refinitiv Eikon, FIX, REST/JSON, ProtobufArchitectureEvent‑driven micro‑services, REST/gRPC APIs, domain‑driven design

Soft Skills

• Sharp analytical and numerical reasoning.
• Clear written and verbal communication—able to brief quants and traders concisely.
• Calm under time pressure; obsessive about detail and test coverage.

Who We Are

HolistiTechis a boutique consultancy specialising in capital‑markets technology and data analytics. Our team has decades of investment‑banking experience across trading, risk, and market‑data systems. Join us at a high‑growth stage and shape both our engineering culture and the next generation of fintech solutions.