What we shipped

Simulations are now billed while they run and priced by how hard you push them, the wallet has been rebuilt as a live instrument, and onboarding no longer costs credits.

• Runs are metered while they run

  Features

  A simulation used to cost the same whether you watched it for ten seconds or left it going all afternoon. It now costs an entry charge plus a small amount every 30 seconds it keeps running, and stops costing the moment you stop it. Pausing is free, and resuming is not billed as a new run.

• Heavy runs cost more than light ones

  Features

  The rate scales with what the run actually pushes: traffic and the size of the system carrying it. An ordinary design at moderate load stays at the base rate; 100 requests a second costs three times that, and the multiplier is capped so a runaway design cannot empty a wallet before you can react. The wallet shows the multiplier live while it applies.

• The wallet is an instrument now

  Features

  A dial reads your balance against its high-water mark, a trace shows where it has been, and a telemetry column reports what is drawing on it right now - the rate, the load multiplier, traffic, node count, and how much runtime the balance buys at that load rather than at the base rate.

• The tutorial no longer spends your credits

  Fixes

  The getting-started tour drives the real app, including starting a simulation, so a new account was paying for its own onboarding. Tutorial-driven runs are free.

• Two metering defects

  Fixes

  A run left at high traffic could collide with the header's live metrics and paint over the credit balance; the header now clips instead. Separately, concurrent charges could exhaust the database connection pool and stall until they timed out - the balance is now read on the connection already held.

Simulation and AI runs now draw from a Flow Credits balance, 22 new components are reserved in the library, and two features have been withdrawn for a rebuild.

• Flow Credits and your wallet

  Features

  Every account now has a credit balance, shown in the header and openable from there. Simulation runs and AI calls draw from it, each priced in the wallet's own list, and every movement is written to a ledger you can read. New accounts start with 200 credits.

• Credit coupons

  Features

  Redeem a coupon code in the wallet and the credits land immediately. Codes can be single-use or shared, and can carry an expiry.

• 22 new components reserved

  Features

  The library now lists 130 component types, up from 108. The 22 additions - Temporal, Airflow, dbt, Snowflake, Databricks, Elasticsearch, Consul, etcd, gRPC, GraphQL, WebSocket, MQTT, TimescaleDB, PlanetScale, PgBouncer, Debezium, Trino, PagerDuty, OTel Collector, Harbor, SonarQube and Ray - are visible and marked Coming Soon while their simulation behaviour is built.

• Interview is now Test Your Skills

  UI/UX

  The graded system-design mode kept getting mistaken for a hiring feature. Same timed challenges, same rubric, a name that says what it is.

• What-if and the SLO calculator are on hold

  Improvements

  Both have been withdrawn for now. What-if applied replica overrides that the simulation engine honoured but nothing else did, so a design could pass in What-if and fail the moment you ran it for real; the SLO calculator graded runs against targets it could not verify against live data. Rather than leave two features quietly giving misleading answers, they are out until each is rebuilt on the new engine. Everything they touched still works: node capacity is edited in the config panel, and run results are unchanged.

• Metering that cannot be skipped

  Improvements

  Charges settle on the server before the work runs, and a failed run refunds itself. Concurrent runs cannot overdraw a balance.

A platform-wide security and reliability pass. Stronger protection around accounts and administrative actions, a new way to connect your own tools, and a great deal of unused surface removed. Nothing you use changed shape.

• Improved application security

  Security

  Hardened the app so injected content cannot be executed, and removed third-party code paths the product no longer needs.

• API keys you can actually use

  Integrations

  Create a key in your account and drive your projects, simulations and analysis from a script or your CI. Keys can be revoked at any time and show when they were last used.

• Administrative actions need an administrator

  Security

  Changing a plan or removing an account now requires a named administrator, and every such action is recorded.

• A smaller attack surface

  Security

  Unused entry points were removed from the platform. What cannot be reached cannot be misused.

• More reliable intelligence features

  Improvements

  Anomaly, saturation and root-cause requests now fail fast and recover instead of hanging.

• Honest AI reporting

  AI

  When a model cannot support a claim, the product says so instead of quietly showing a number.

• Safer releases

  Improvements

  Broken builds are now caught before they can reach you.

SystemFlow now loads from your browser first. Everything already downloaded stays downloaded, so a returning visit paints immediately and only fetches what actually changed.

• Instant returning visits

  Performance

  Coming back to SystemFlow paints from local storage instead of re-downloading the product.

• Dramatically faster startup

  Performance

  Roughly three seconds of start-up work and several megabytes of download removed from every visit.

• Predictive loading

  Performance

  The next page you are likely to open is prepared quietly in the background.

• Offline support

  Features

  The app opens and your recent data is readable with no connection at all.

• Edits survive a dropped connection

  Features

  Changes made offline are queued and sent when you reconnect.

• Private by account

  Security

  Cached data is separated per account and cleared when you sign out.

• Storage that looks after itself

  Improvements

  Local storage stays inside sensible limits and repairs itself if it is damaged.

• Lighter updates

  Performance

  A routine release no longer re-downloads the parts that did not change.

The simulator now checks whether a design makes sense before it runs one: no traffic source, a client wired straight to a database, a circular dependency, all stopped with the exact fix.

• Invalid designs are blocked, not silently run

  Features

  A design that cannot work is explained and stopped before it wastes your time.

• The Advisor got much more specific

  AI

  Findings name the component, the problem and the fix instead of offering general advice.

• Node-specific crash messages

  AI

  When a component fails, the reason reflects how that technology really fails.

• Validation follows you

  UI/UX

  Warnings appear on the component itself, not only in a list.

• A more honest canvas

  UI/UX

  The canvas shows real state rather than decorative animation.

The AI platform ships: a failure detector with published results, live severity and root-cause verdicts on every run, and one source of truth behind every panel.

• A detector with receipts

  AI

  Failure detection whose accuracy is measured on data it never trained on, and published in the product.

• Live failure predictions

  AI

  During a run, every service is scored for failure risk, severity and likely root cause.

• Trained on a small internet

  AI

  Models learned from a simulated fleet the size of a real one, failures included on purpose.

• One source of truth

  Improvements

  Every panel reads the same component data, so numbers agree wherever you look.

• A new upgrade experience

  UI/UX

  Upgrading is a single clear dialog instead of a detour.

SystemFlow now teaches itself. A hands-on tutorial, a full keyboard, and a canvas that finally moves like a design tool.

• Interactive tutorial

  Features

  A guided walkthrough that builds a real system with you instead of showing slides.

• Demo mode

  Features

  Try the whole product on a sample system without touching your own work.

• A real keyboard

  Features

  Copy, paste, duplicate, undo, nudge, zoom and run, all from the keyboard.

• Multi-selection

  Features

  Select many components and move, configure or delete them as one.

• Help Center

  Features

  Searchable answers and every shortcut in one panel, on the ? key.

• Dependency tracing

  Features

  Click a component to light up everything it depends on.

• A canvas with weight

  UI/UX

  Movement, depth and feedback that make the canvas feel physical.

A rebuilt sign-in, email that actually arrives, teams you can invite, and a canvas that remembers exactly where you left it.

• Redesigned sign-in

  UI/UX

  A clearer, faster path into the product on any device.

• Reliable email

  Improvements

  Verification, reset and invitation emails now arrive promptly and consistently.

• Your canvas stays where you put it

  Features

  Zoom, position, mode and zones are all restored exactly as you left them.

• Invite your team

  Features

  Send an invitation and give a colleague the right level of access.

• Your work is yours

  Security

  Improved protection around personal data and account access.

The interface got out of the way: floating panels, a tidier toolbar, a rebuilt dashboard and a much bigger template library.

• Canvas-first layout

  UI/UX

  Panels float over the canvas and collapse away, so the diagram is always the biggest thing on screen.

• A much bigger template library

  Features

  Dozens of reference architectures, from a three-tier app to a full social platform.

• Pro tier

  Features

  Advanced components, deeper simulation controls and the AI reviewer.

• New dashboard

  UI/UX

  Projects, recent activity and usage in one place.

• Zones everywhere

  Features

  Zones now work in every canvas mode, including 3D.

Large diagrams become manageable: group components into zones, arrange them automatically, and navigate without losing your place.

• Zones

  Features

  Draw resizable regions around related components to show boundaries such as a VPC or an environment.

• Auto-arrange

  Features

  Tidy a sprawling diagram into a readable layout in one action.

• Right-click menus

  Features

  Common actions are on the component itself instead of buried in a panel.

• Mini-map

  UI/UX

  Jump anywhere on a large diagram without endless scrolling.

• Layout fixes

  Bug Fixes

  Wide architectures no longer render stacked on top of each other.

Every component type gains an engineering profile: what it is limited by, which signals matter, and how its failures spread to everything downstream.

• Failure knowledge, built in

  AI

  Over a hundred component types now carry a profile of how they behave under stress and how they break.

• Smarter diagnosis

  AI

  When something fails in a simulation, the explanation reflects how that technology actually fails.

• Richer component details

  Features

  Each component shows its bottlenecks, health signals and typical failure modes.

• Interface refresh

  UI/UX

  Panels and inspectors redesigned around the new detail.

A full administration area: manage users, plans, support requests and platform activity from inside the product.

• Admin console

  Features

  See users, plans and activity at a glance.

• Support queue

  Features

  Raise and track support requests in the product instead of over email.

• Platform activity

  Analytics

  Live view of what is happening across the workspace.

• Controlled access

  Security

  Administrative areas are available only to the people who should see them.

The reference screens are back, so you can see where the interface is heading.

• Design previews restored

  UI/UX

  Browse upcoming layouts for the dashboard, admin and onboarding screens.

The sign-in screen returns to its original design, and gets far more stubborn about actually letting you in.

• The original sign-in design, back

  UI/UX

  The layout people preferred, restored.

• No more sign-in loops

  Bug Fixes

  Fixed a case where a valid session could bounce you back to the login screen.

• Works when things are slow

  Improvements

  Sign-in survives a slow or briefly unavailable connection instead of failing outright.

Authentication was rebuilt on a managed identity service. Sign-in is faster, sessions are safer, and password resets work properly.

• Enhanced account protection

  Security

  Accounts are secured by a dedicated identity platform.

• Password reset that works

  Features

  Request a reset link and set a new password without contacting support.

• Sessions that persist

  Improvements

  Stay signed in across tabs and browser restarts.

• Sign in with Google or GitHub

  Integrations

  Use an existing account instead of another password.

Interface cleanup and a round of reliability work across the app.

• Interface polish

  UI/UX

  Spacing, contrast and alignment corrected throughout.

• Quicker to load

  Performance

  Unused assets removed from the app, so it starts faster.

• Improved application security

  Security

  Routine protective updates across the platform.

The app interface was reworked: a clearer canvas, a real properties panel, and example systems to start from.

• New workspace layout

  UI/UX

  Canvas, configuration and simulation each have a proper place on screen.

• Properties panel

  Features

  Select any component and configure it in place.

• Example systems

  Features

  Open a ready-made architecture instead of starting from an empty canvas.

A completely new marketing site, and a clear-out of everything that no longer belonged.

• Rebuilt marketing site

  UI/UX

  Faster, clearer, and honest about what the product does today.

• Lighter pages

  Performance

  Public pages load noticeably quicker.

• Accurate content

  Improvements

  Pages describe features that actually exist.

A stability release. Fewer rough edges, fewer surprises after an update.

• More reliable updates

  Improvements

  Releases are checked end to end before they reach you.

• Startup fixes

  Bug Fixes

  Resolved issues that could leave the app in a half-loaded state.

Your work moves to a real cloud database, and the intelligence service moves alongside it. Projects are no longer tied to one machine.

• Work follows you

  Features

  Sign in anywhere and your projects are there.

• Sturdier storage

  Improvements

  Projects and simulation history are stored on managed infrastructure with backups.

• Intelligence, always on

  AI

  Analysis runs as its own service, so heavy work never slows the canvas down.

The pages you only see when something goes wrong were designed properly, and the account area got its own home.

• Designed error pages

  UI/UX

  Not found, access denied, too many requests, server error and maintenance now explain what happened and what to do next.

• Account area

  Features

  A dedicated set of pages for your profile, usage, billing and notifications.

• Design gallery

  UI/UX

  Reference screens showing where the product is going.

SystemFlow becomes a product you can buy. Plans, upgrading and usage all arrive together.

• Plans and upgrading

  Features

  Move to a paid plan from inside the app, with a real checkout.

• Manage your subscription

  Features

  Change or cancel your plan without emailing anyone.

• See your usage

  Analytics

  Track how many projects and simulations you have used against your plan.

• Pricing pages

  UI/UX

  Clear pages explaining what each plan includes.

Sign-up, sign-in and email verification are now a complete flow, and your account is protected properly.

• Sign up and sign in

  Features

  Create an account with an email address and a password.

• Email verification

  Features

  Confirm your address before your account goes live.

• Protected accounts

  Security

  Improved account protection across the platform.

• Session that lasts

  Improvements

  Stay signed in between visits instead of logging in every time.

Motion and pacing on the landing page: typed headlines, an ending worth reaching, and navigation that keeps up with you.

• Animated introduction

  UI/UX

  The headline types itself out and the page ends on a call to action instead of trailing off.

• Auto-advancing sections

  UI/UX

  Sections cycle on their own, and stop the moment you take over.

• Scrolling fixes

  Bug Fixes

  Scroll position and navigation no longer fight each other.

The sign-in screen was redesigned, and navigation gained a full-screen menu.

• A cleaner sign-in

  UI/UX

  Less chrome, bigger targets, and a clearer path to creating an account.

• Full-screen navigation

  UI/UX

  A menu overlay that works properly on small screens.

• Fewer mis-taps

  Improvements

  Buttons and links were resized for touch.

A public website for SystemFlow, so there is somewhere to send people who have not signed up yet.

• New marketing site

  UI/UX

  A proper landing experience explaining what SystemFlow does.

• Consistent branding

  UI/UX

  The site and the app finally look like the same product.

The beginning of monitoring: SystemFlow can now take readings from real servers, not only simulated ones.

• Live metric collection

  Features

  Lightweight agents read CPU, memory, disk, network and request metrics from machines you actually run.

• An intelligence service

  Features

  A dedicated service to analyse those readings, separate from the app so it can grow on its own.

• A shared vocabulary

  Analytics

  Every metric has one canonical name, so a reading means the same thing everywhere in the product.

SystemFlow can now email you: account confirmations, password resets and the occasional thing worth knowing.

• Account emails

  Features

  Confirm your address and reset your password from your inbox.

• Reliable delivery

  Improvements

  Messages are sent through a proper mail service instead of best effort.

Projects now persist. Close the tab, come back tomorrow, and your architecture is exactly where you left it.

• Saved projects

  Features

  Every diagram is stored against your account and reloads automatically.

• Multiple projects

  Features

  Keep separate designs side by side instead of overwriting one canvas.

• No more lost work

  Improvements

  Changes are saved as you make them, not only when you remember to.

A cleanup pass on the canvas. Visual noise that got in the way of designing was removed.

• Less clutter

  UI/UX

  Overlays that covered your diagram while you worked are gone.

• Smoother to draw on

  Performance

  Panning, zooming and dragging feel lighter on large diagrams.

The canvas becomes the product. Building a system and running traffic through it now happen in the same place, without switching screens.

• One workspace

  Features

  Design, configure and simulate from a single canvas instead of separate pages.

• A real component library

  Features

  Drag infrastructure components straight onto the canvas.

• Faster to get started

  UI/UX

  The interface was rebuilt around the thing you actually came to do.

The first build. Design a system on a canvas, create an account, and keep your work between visits.

• The design canvas

  Features

  Lay out an architecture visually instead of describing it in a document.

• Accounts

  Features

  Create an account and sign in to keep your work.

• A home for the product

  UI/UX

  A landing page, a sign-in page and a workspace, all in one place.