Build powerful rules, configure complex business logic, and manage multi-tenant products with ease. Stellwerk adapts to your business needs.
Change inputs. The result updates instantly using the same style of expression semantics the engine runs (client simulated). In production you POST inputs and get a full context + applied rules.
final_price := (base_price * (1 - discount_rate)) + unlock_fee
:=.final_price).From idea to production in three steps
Model your logic visually, wire inputs and exports, then evaluate it via a fast API.
Design your flow
Create small, readable rule nodes and connect them to form branches and joins. Only explicitly exported variables propagate.
Wire inputs and exports
Map product inputs, declare exports, and validate deterministically with a graph-aware linter.
Evaluate and monitor
Call the API for real-time decisions. Join strategies like wait_then_pick choose the best path.
Start free, scale later
Free while in beta. Plus and Pro plans are coming soon. Pricing will scale primarily by calculation runs / month and advanced feature unlocks.
For trying things out
More power and scale
For production teams
Prefer to wait for Plus/Pro? Join the waitlist and we’ll keep you posted.
Set prices in real time based on usage, demand, or customer segment.
Automate credit scoring and eligibility checks for instant decisions.
Calculate recurring charges, discounts, and usage-based fees.
Evaluate risk and premiums with flexible, auditable rules.
Award points, bonuses, or tier upgrades based on custom logic.
Gate features or content based on user attributes and entitlements.
Balance loot drops, crafting costs, XP scaling, and in‑game shop pricing with tunable, testable formulas.
A focused rules & calculation engine that stays flexible as your logic evolves—without turning into a monolith or a black box.
Model flows as a graph of readable rule nodes. Export only what matters. Avoid giant unreadable formulas.
Concurrent paths resolve via scored join selection—no mystery race conditions.
Projection helpers (items[*].price) with safe SUM, MIN, MAX, FIRST, TAKE and more—no custom loop DSL.
Scoped data & auth baked in. Separate products, calculations, and API keys per tenant.
Explicit assignments & exports produce a traceable context—easy to diff and reason about.
Lean evaluator with safe expression sandboxing and predictable performance.