Python development
From FastAPI services to data and automation tooling, we build robust Python backends — the kind with tests, typing, and observability rather than a fragile script that only the author understands.
What you get
- FastAPI / Django backends and APIs
- Data pipelines and automation
- AI/ML service integration
- Tests, typing, and clean structure
How we deliver.
A structured engagement from discovery to deployment — no surprises, no scope fog.
Architecture & API design
We define the service boundaries, API contracts (OpenAPI spec), database schema, and async task strategy before building — so the codebase scales from day one.
Core service implementation
We write the application code — endpoints, business logic, database models, auth middleware — with full type annotations, Pydantic validation, and structured logging.
Background jobs & task queues
Long-running tasks (report generation, email dispatch, data processing) run asynchronously via Celery or ARQ with retry logic and dead-letter handling.
Testing & quality gates
Unit tests, integration tests, and API contract tests with pytest. CI runs linting (ruff), type checking (mypy), and test suites on every push.
Containerization & deployment
Docker images, health checks, and deployment manifests for your target platform — whether that's AWS ECS, Railway, or a bare VPS.
Where this applies.
AI/ML model serving APIs
FastAPI services that wrap ML models with input validation, batching, caching, and health checks — production-ready inference endpoints.
ETL & data pipeline backends
Scheduled data pipelines that extract from source systems, transform and validate data, and load into warehouses or analytics databases.
Internal tooling & admin APIs
Backend services for internal dashboards, admin panels, and operations tools — with role-based access control and audit logging.
Microservice extraction
Breaking a monolithic backend into focused, independently deployable Python services with clear API contracts and shared schema registries.
Technical depth.
FastAPI with async I/O
Non-blocking request handling with async/await for high-concurrency workloads — database queries, external API calls, and file I/O run in parallel without blocking.
Pydantic v2 data validation
Every request and response is validated through Pydantic models — catching malformed data at the boundary, generating OpenAPI docs automatically, and ensuring type safety.
Alembic migration management
Database schema changes are tracked as versioned migrations with Alembic — reviewable in PRs, reversible in production, and safe for team collaboration.
Structured observability
Structured JSON logging, OpenTelemetry tracing, and Prometheus metrics — so you can trace a request from API gateway to database and back.
Common questions.
Q.FastAPI or Django — which should I choose?
FastAPI for API-first services, microservices, and AI backends. Django for admin-heavy applications, content management, or when you need the ORM and built-in admin panel.
Q.Do you write tests?
Always. Every project ships with unit tests, integration tests, and API contract tests. We target 80%+ coverage on business logic and 100% on critical paths.
Q.Can you maintain or refactor an existing Python codebase?
Yes. We regularly take over legacy Python projects — adding types, tests, documentation, and modernizing to current best practices without breaking existing functionality.
Q.How do you handle database migrations?
Alembic for FastAPI projects, Django migrations for Django. Schema changes are code-reviewed, tested against production-like data, and safely reversible.
Featured projects.
AI infrastructure cleanup: cost & reliability overhaul
A production AI system that was slow, over-budget, and failing silently — audited, root-caused, and rebuilt into something dependable.
Chrome Extension for automated CRM lead extraction
A Manifest V3 browser extension that lets sales representatives clip prospect contacts from web directories directly into their CRM with a single click.
Cross-platform mobile app for real-time logistics tracking
A high-performance React Native / Expo app that lets field operators track inventory and log tasks in real time, even while offline.
What our partners say.
“We hired Lesscode to build our Next.js customer portal. Code quality is top-notch, types are fully verified, and performance is outstanding. They worked like an extension of our team.”
“Our Chrome Extension for CRM lead collection was delivered fast and compiled with Manifest V3. Sales reps love it—saving 10+ hours per week per rep. Flawless execution.”
“Our field agents needed an offline-first app that could work deep inside remote warehouses. The React Native app Lesscode delivered is fast, syncs reliably, and handles data conflicts seamlessly.”
“They took our rough SaaS MVP idea and built it into a production-grade NestJS / Prisma web app. Handing over fully-tested code with Stripe integrations was incredibly smooth.”
“FastAPI endpoints that integrate our core systems. Clean documentation, secure auth gates, and handled load surges without slowing down. Absolute professionals.”
Building something ambitious, or fixing something that's gone sideways?
Tell us where you are and where you're trying to get to. We'll tell you honestly whether — and how — we can help.