
Modern Approaches to Software Development
With examples from a large fintech

With examples from a large fintech
With examples from a large fintech
Modern development layers
Brute force: fit and failure
Design: requirements, domain, Clean Architecture
Storage, NoSQL, microservices
Delivery, infra, QA, security
When it works and when it breaks
Linear cycle and pain
Business wants the neighbor's, only better
Requirements outrun code
Deploy stays an event
Few tests, high prod risk
You don't always need Clean Architecture
Prototypes and MVPs, 2–4 weeks
RnD experiments with hypotheses
Automation scripts, one-off tasks, promo pages
Maintaining beats throwing it away
When investments in design pay off
Layers of meaning
Requirements gathering and formalization
Use cases
Domain model and language
Patterns and ADRs
Dependencies point inward
Entities — business objects and invariants
Use Cases — application business rules
Interface Adapters — controllers, presenters
Frameworks & Drivers + Dependency Rule
From file system to NoSQL and Data Mesh
Engine per access pattern
Key-Value — fast lookup
Column-Family — wide rows
Document — flexible schema
Graph — relationships and traversals
Monolith → SOA → Microservices
Solutions create complexity
Monolith — simple deploy
SOA — heavy middleware
Microservices — harder ops
DDD sets service boundaries
From FTP to DevOps and IaaC
What you can't skip
Build quality in
Unit tests — fast pyramid base
Integration / contract — service boundaries
E2E — few but critical scenarios
Production testing: canary, shadow, chaos
DevSecOps by design
SAST / DAST in CI
SCA — dependencies and CVEs
Secrets — Vault, KMS
Threat modeling + least privilege
From Warehouse to Data Mesh
Warehouse — structured, slow
Lake — schema-on-read
Lakehouse — hybrid
Mesh — self-serve product
Brute force belongs in prototypes
Design makes decisions explicit
Storage is chosen for the task
Delivery and infrastructure became code
Quality and security live inside the loop
every practice adds a step to the same loop
Architecture, data, DevOps
Clean Architecture + Microservices
Domain-Driven Design
Martin Kleppmann — Designing Data-Intensive Applications
Accelerate (DORA) + Data Mesh
polomodov.tech
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Alexander Polomodov, Technical Director & Fellow, T-Technologies
@book_cube