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JustSoftLabJustSoftLab
JustSoftLabJustSoftLab
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Services/Platform Engineering/SaaS Product Engineering

SaaS platforms built to scale.

Multi-tenant architecture, subscription billing, role-based access, usage metering, white-labeling. We build the infrastructure so you focus on the product. From MVP to 10,000 tenants without rewriting everything.

50+

SaaS products launched to production

10K+

Tenants served by delivered platforms

< 16 wks

From concept to paying customers

99.95%

Uptime across multi-tenant platforms

What we build

SaaS engineering at every stage.

Multi-tenant architecture

Shared schema, schema-per-tenant, or DB-per-tenant — right isolation model for your compliance and scale needs. Row-level security, tenant context propagation, and per-tenant customization.

Subscription & billing

Stripe, Chargebee, or custom billing with plans, proration, trials, usage-based pricing, and dunning. Revenue operations that don't leak money or anger customers.

Usage metering

Real-time metering of API calls, compute, storage, seats. Event-driven architecture with accurate billing events, usage dashboards, and per-plan quotas with soft/hard limits.

White-label capability

Custom domains, branding, theming, and feature flags per tenant. Enterprise customers get their own-looking product. You get one codebase to maintain.

Enterprise features

SSO (SAML, OIDC), SCIM provisioning, audit logs, role-based access control, data residency. The features that unlock $50K+ enterprise deals.

Admin & operations

Customer success tooling — tenant search, impersonation (audited), usage analytics, support dashboards. Your ops team operates the platform without engineering tickets.

Sound familiar?

SaaS problems we solve every quarter.

Our MVP has 50 tenants and the database is crying. We need to re-architect for scale.

We migrate to a proper multi-tenant architecture incrementally — tenant sharding, read replicas, caching layers. Most platforms scale 10x without rewriting business logic.

Enterprise leads keep asking for SSO, audit logs, and SOC 2. We're losing $100K+ deals.

We build the enterprise feature set in 6-8 weeks — SAML/OIDC SSO, SCIM, audit trail, role-based permissions. You start closing enterprise deals the same quarter.

Billing is a mess. Customers are being over- or under-charged and nobody can explain why.

We rebuild billing with a proper event-driven architecture — immutable usage events, auditable billing logic, reconciliation reports. Billing accuracy goes from "usually right" to 100%.

Tech stack

Tools we use in production.

Next.js
NestJS
FastAPI
Ruby on Rails
PostgreSQL
Redis
ClickHouse
Stripe
Chargebee
Paddle
Auth0
WorkOS
Clerk
AWS
Kubernetes
Terraform
Datadog
Sentry
PostHog

Ready to build

Let's build a SaaS platform ready to scale.

45 minutes with our SaaS architects. We'll review your product vision, outline a multi-tenant architecture, and estimate time-to-revenue honestly.