u/malphas_x

I'm a CS student learning Java and Spring Boot and I'm interested in understanding how production fintech systems are built.

For engineers with experience building payment or banking systems, what technical and domain knowledge would you recommend studying?

I'm particularly interested in topics such as ledgers and double-entry accounting, payment lifecycles, settlement and reconciliation, ISO 8583, idempotency, concurrency, Kafka, Redis, PostgreSQL and distributed systems.

I'm also planning to build a wallet/payment-system project for learning purposes. What concepts would make such a project closer to a real production fintech system?

I'm only looking for technical learning advice and industry knowledge.

Hey everyone! Is anyone here currently working in fintech, particularly in backend/software engineering?

I’m a final-year CS student and I’m currently focusing on Java + Spring Boot with the goal of getting into fintech backend development.

I’d really appreciate guidance from someone already in the industry, especially around:

• What skills and technologies fintech companies actually look for in fresh graduates
• What fintech-specific concepts I should learn
• What kind of projects would make my profile stronger
• How a fresher can break into fintech roles
• Anything you wish you had learned before entering fintech

If anyone here works in fintech and wouldn’t mind sharing their experience, I’d really appreciate it. Thanks!

Hi everyone,

I’m a final-year Computer Science student and I’m planning to build my career specifically in fintech/backend engineering.

I’m currently learning Java + Spring Boot for enterprise and fintech roles. I already have backend development experience with technologies like FastAPI, Express.js and NestJS, but I want to specialize more deeply in fintech rather than remain a general full-stack/backend developer.

I’d especially like advice from people currently working in fintech, banking, payments, wallets, card processing, or financial infrastructure.

A few things I’d love guidance on:

1. What do fintech companies expect from fresh graduates/junior backend developers besides Java + Spring Boot?
2. Which fintech/domain concepts should a developer understand? For example: ledgers, double-entry accounting, payment lifecycle, settlement, reconciliation, refunds/reversals, chargebacks, ISO 8583, transaction processing, etc.
3. Which backend technologies should I prioritize? Kafka, Redis, PostgreSQL, Docker/Kubernetes, microservices, distributed systems, observability, cloud, etc.
4. What kind of project would actually impress a fintech interviewer? I’m considering building a wallet/payment system with proper ledger entries, transaction states, idempotency, reconciliation, event-driven processing, and failure handling instead of another CRUD project.
5. How important are DSA, system design, databases and concurrency for entry-level fintech interviews?
6. What are some things you only learned after actually working in fintech that you wish you had known earlier?
7. Finally, is specializing in fintech early in my career a good idea, or would you recommend becoming a strong general backend engineer first and specializing later?

I’d really appreciate answers from engineers currently working in fintech/payments/banking, especially Java/backend engineers.

Thanks!

Hi everyone,

I’m a final-year Computer Science student and I’m planning to build my career specifically in fintech/backend engineering.

I’m currently learning Java + Spring Boot for enterprise and fintech roles. I already have backend development experience with technologies like FastAPI, Express.js and NestJS, but I want to specialize more deeply in fintech rather than remain a general full-stack/backend developer.

I’d especially like advice from people currently working in fintech, banking, payments, wallets, card processing, or financial infrastructure.

A few things I’d love guidance on:

1. What do fintech companies expect from fresh graduates/junior backend developers besides Java + Spring Boot?
2. Which fintech/domain concepts should a developer understand? For example: ledgers, double-entry accounting, payment lifecycle, settlement, reconciliation, refunds/reversals, chargebacks, ISO 8583, transaction processing, etc.
3. Which backend technologies should I prioritize? Kafka, Redis, PostgreSQL, Docker/Kubernetes, microservices, distributed systems, observability, cloud, etc.
4. What kind of project would actually impress a fintech interviewer? I’m considering building a wallet/payment system with proper ledger entries, transaction states, idempotency, reconciliation, event-driven processing, and failure handling instead of another CRUD project.
5. How important are DSA, system design, databases and concurrency for entry-level fintech interviews?
6. What are some things you only learned after actually working in fintech that you wish you had known earlier?
7. Finally, is specializing in fintech early in my career a good idea, or would you recommend becoming a strong general backend engineer first and specializing later?

I’d really appreciate answers from engineers currently working in fintech/payments/banking, especially Java/backend engineers.

Thanks!