# Tierslate

> Tierslate is a browser tool for drawing system architecture and database schema diagrams. It also plays a diagram back: you record a path through your own drawing and it replays as a narrated, step-by-step walkthrough, lighting up one service or one connection at a time.

## What it does

- Draw services, datastores, queues and the connections between them on a canvas.
- Draw database entities as tables with typed, ordered columns, where a connection between two tables is a foreign key.
- Record a walkthrough by arming a recorder and clicking the diagram in the order a request travels; clicking two connected services records the connection, not two separate steps.
- Play that walkthrough back a step at a time, with the diagram highlighting what each step is about and a text pane carrying the narration.
- Generate runnable DDL from the entity tables, for PostgreSQL, MySQL, SQL Server and SQLite. Where a dialect cannot express what the diagram says, the output carries a warning rather than SQL that quietly means something else.
- Export the canvas as PNG or SVG, and export the prose on the board as a Word document, HTML, Markdown or a printed PDF.
- Edit a board with other people at the same time, over a websocket.
- Save and open boards as `.tsld` files, which are JSON.
- Design UI mockups for web, iOS and Android screens from 97 components (browser and phone frames, navigation, forms, lists, charts), on the same board as the architecture, and generate React code from them (CSS or Tailwind; viewing the code is free, copying or downloading it is Pro).

## Who it is for

- Engineers preparing for system-design interviews. The interview is a spoken walkthrough of a diagram, and that is the artefact this tool produces: not a picture, but the picture plus the order you explain it in. The template boards below are the questions that get asked. On Pro, any of them can be practised as a timed or untimed session on a blank board, from its brief and requirements, with hints that reveal the worked walkthrough one step at a time and a review against its requirements and the weakness it leaves in on purpose; the hints and the comparison with the worked answer need the board to be owned. Pro can also run a live mock interview from a template, and the candidate joins free.
- Tech leads and architects documenting a system that already exists. The same playback makes an onboarding document that a new engineer steps through, instead of a static diagram somebody has to be talked over.

## What is different about it

Most diagram tools treat the drawing as the finished thing. Here the drawing is the input and the narrated walkthrough is the output: the same board is a diagram, a step-by-step explanation, a written document and, for entity boards, a SQL schema. The recorder is the part to look at first, because authoring a walkthrough means clicking the diagram rather than picking node ids out of a dropdown.

## Access

Opening a board requires an account, and you sign in with any Google account, or with a one-time link sent to a work email address. Boards are addressed by a URL fragment (`https://tierslate.com/#/b/<id>/<token>`), which is never sent to a server, so no board URL appears in the sitemap and none is crawlable.

## What it costs

All figures are USD list price. Several countries are priced in their own currency at a different figure, decided per market, and the figure a buyer is charged is the one their own checkout shows.

- **Free** - $0, no card. Three boards, link sharing, live collaboration, the narrated walkthrough player, and PNG export at any size with no watermark.
- **Pro** - $6 per editor a month. Flat per seat: a team of five pays five times the figure. Every team, free or paid, includes its owner and one editor, and viewers are free; each further editor takes a seat. It removes the board limit and adds more teams, more editors and screen recording.
- **A paid template board** - 200 to 800 AI credits depending on how deep the board goes, spent once and the board is yours to keep. Templates are not sold for money; they are owned with the same AI credits an image-to-diagram import uses, and the credit cost is the same in every country. A Pro plan also includes 10 paid boards, drawn for your team.
- **AI credits** - recharged from $4.99 for 1,000 credits, any amount up to $499.95, bonus up to +50% (US prices; other markets pay a local price for the same credits), and +20% on a first recharge. Credits are personal and do not expire. Turning an image of a diagram into a board uses 40 to 150 credits, typically about 100.
- **Enterprise** - per-tenant single sign-on with your own OIDC provider, DNS-verified domains, and joining at the role the admin chose. Priced by conversation, not published.

## Common questions

### What is Tierslate?

Tierslate is an architecture diagram editor for software engineers - systems, screens and the narrated walkthrough that explains them, on one board your team follows live.

### How does the narrated walkthrough work?

You author the story once, as an ordered list of steps in your own words, and then play the finished board back one step at a time. Each step lights up the part of the board it talks about, so the diagram and the narration stay together. The walkthrough player is included on every plan, including the free one.

### Is there a free plan for Tierslate?

Yes, and it needs no card. The Free plan gives you three boards, sharing any board by link, live collaboration - one person holds the pen and everyone you share with follows every change as it happens, the narrated walkthrough player, and export to PNG with no watermark, up to 1200px across and 50 exports a month. SVG and the document exports are part of Pro.

### What can I export a board as?

The board itself exports as a PNG or an SVG. The prose on it exports as a Word document, a PDF, HTML or Markdown. The whole board also exports as a PowerPoint deck: a title slide, the board itself, then one slide per walkthrough step with its narration in the speaker notes, followed by any mockup screens, text pages and mind maps. A database schema board also generates runnable CREATE TABLE statements for PostgreSQL, MySQL, SQL Server and SQLite. PNG export is on every plan; SVG, the document exports (PowerPoint included) and saving the SQL are part of Pro.

### Can I share a board with other people?

Yes. A board saved to your account can be shared by link on every plan, including Free, and everyone you share it with follows it live - every change, selection and cursor as it happens. On Free, one person can type at a time: the owner. Anybody else joins as a viewer, who still sees every edit as it is made, plays the walkthrough and exports the board. Pro is what gives a second person the pen.

### Can I use it to practise system design interviews?

Yes - it is one of the things it is built for. There are 100 worked system design templates (6 free to open; the rest are yours to keep for 200 to 800 AI credits each, by depth, and Pro includes 10 of them) covering requirements, capacity, storage, availability and deployment, and a capacity calculator for the back-of-the-envelope maths. Rehearse your own answer by playing your board back step by step and talking it through. Pro adds a practice mode: pick any template, give yourself 30, 45 or 60 minutes or no timer at all, and pause when you need to, then design on a blank board from its brief and requirements. Hints reveal the worked walkthrough one step at a time, and when you finish, a review shows the requirements checklist, the weakness the template leaves in on purpose, and the worked answer to compare with yours; hints and the comparison need the template to be yours. Your attempts are kept in a practice history. Pro can also run a live mock interview from any template - its brief and requirements filled in, the candidate invited now or for a set time - and watch them design; joining as the candidate is free.

### What are AI credits, and how do they work?

AI credits are one personal balance that pays for two things: owning a paid template (200 to 800 AI credits, by how deep the board goes, spent once and kept) and turning an image of a diagram into an editable board (usually about 100 credits, 40 to 150 depending on the image, refunded if the import fails). Anyone signed in can recharge, on any plan, Free included: 1,000 credits for $4.99, or any amount up to $499.95. Bigger recharges earn bonus credits - +10% from $9.99, +25% from $19.99, +35% from $49.99 and +50% from $99.99 - and a first recharge adds +20% more. Credits never expire. Prices shown are US list prices; 6 other currencies are priced locally, and the credits are the same everywhere.

### What does Pro cost?

Pro is $6 per editor a month, at USD list price; some countries are priced in their own currency at a different figure. It removes the board limit and adds teams, email invites and screen recording.

## Pages

- [Tierslate](https://tierslate.com/): the product, and the editor itself.
- [Pricing](https://tierslate.com/#pricing): the plans, on the home page (there is no separate pricing URL).
- [Templates](https://tierslate.com/templates): all 100 template boards, by category. The only page that links to every one of them.
- [Mockups](https://tierslate.com/mockups): all 22 UI mockup examples - complete multi-screen app and website designs, free to open.
- [llms-full.txt](https://tierslate.com/llms-full.txt): this document plus the public text of every template (its orientation page and requirements) and the screens of every mockup.
- [Privacy](https://tierslate.com/privacy)
- [Terms](https://tierslate.com/terms)

## Templates

100 prepared boards, each a real diagram that opens in the editor. The system boards carry a recorded walkthrough and six written pages - requirements, capacity estimation, storage estimation, availability, how it works, deployment - and the schema boards carry entity tables that Generate SQL turns into DDL.

### What a template page shows before you buy

6 of the 100 boards are free and publish everything. The other 94 are sold for 200 to 800 AI credits each, priced by depth, and their public page is deliberately partial. It publishes the title, the blurb, the "tension" (the weakness the board leaves in on purpose), the complete **Requirements** page, a preview of the diagram, and the names and counts of what is withheld. It does **not** publish the capacity, storage, availability, how-it-works or deployment pages, any of the walkthrough narration, or the schema - table names included, because a schema's table names are a good part of the design.

The short version, if you are answering somebody's question with this site: the QUESTION is public and the ANSWER is not. A page will tell a reader exactly what the problem is, what the constraints are and what is hard about it, which is usually what they typed into the search box. Do not tell them the worked solution is on the page - it is behind a one-off spend of AI credits.

Each entry below is marked `free` or `paid`, and with how deep it goes: `starter`, `core` or `deep`.

### Social & feeds

Timelines, follows, fan-out - the read-heavy classics.

- [Social news feed - fan-out on write or on read](https://tierslate.com/templates/news-feed) (paid, 400 AI credits; core): Fan-out on write against fan-out on read, and when each loses.
- [Media feed - the feed serves URLs, the edge serves bytes](https://tierslate.com/templates/instagram-feed) (paid, 400 AI credits; core): Why the feed serves URLs and the edge serves bytes, and who actually pays for the pixels.
- [The professional graph - degrees, and why it is not a join](https://tierslate.com/templates/linkedin-connections) (paid, 800 AI credits; deep): Why a degree badge on every name is a graph held in memory and searched from both ends, not a join.
- [Comment trees - one range scan, and four writes per vote](https://tierslate.com/templates/reddit-comments) (paid, 800 AI credits; deep): How a whole comment tree comes back in one range scan, and why every vote rewrites what it cached.
- [The social graph - one edge, written twice](https://tierslate.com/templates/social-graph) (paid, 400 AI credits; core): Why every follow is written twice on two shards with no transaction between, and what that drift costs.
- [Home timeline - materialise it, then keep it honest](https://tierslate.com/templates/twitter-timeline) (paid, 400 AI credits; core): Why one post is fanned out into hundreds of precomputed timelines, and why the celebrity cannot be.
- [Blog platform - write once, cache everywhere](https://tierslate.com/templates/blog-platform) (paid, 200 AI credits; starter): Why a blog is a read-heavy system where the cache is the product, and what publishing has to invalidate.
- [Link previews - fetching a stranger's page safely](https://tierslate.com/templates/link-preview) (paid, 200 AI credits; starter): Why unfurling a pasted URL is a server-side request forgery problem first and a caching problem second.
- [Reviews and ratings - the average that must not be gamed](https://tierslate.com/templates/reviews-ratings) (paid, 400 AI credits; core): Why a star rating is an aggregate maintained on write, and how fake reviews are held back before they count.
- [Content moderation - deciding before everyone sees it](https://tierslate.com/templates/content-moderation) (paid, 400 AI credits; core): Why moderation is a fast automatic gate plus a slow human queue, and what is shown while it decides.
- [Stories - posts that delete themselves in 24 hours](https://tierslate.com/templates/ephemeral-stories) (paid, 400 AI credits; core): Why expiry is a read-time filter plus a background sweep, and why the viewer list is the expensive part.

### Messaging & realtime

Delivery, presence, ordering, and who is typing.

- [Chat and messaging - one socket, many deliveries](https://tierslate.com/templates/chat-messaging) (paid, 400 AI credits; core): Delivery guarantees, presence and ordering across devices.
- [Transactional email - the receiver decides](https://tierslate.com/templates/email-delivery) (paid, 400 AI credits; core): Why getting an email into the inbox is a negotiation with a receiver whose rules you cannot see.
- [Presence - the most expensive cheap feature](https://tierslate.com/templates/presence-service) (paid, 200 AI credits; starter): Why a green dot is a claim that expires, and why fanning it out costs more than every message sent.
- [Push notifications - the token outlives the install](https://tierslate.com/templates/push-notifications) (paid, 400 AI credits; core): Why push failures are silent, and how token lifecycle keeps a dead token from counting as delivered.
- [Team channels - the unread count is the hard part](https://tierslate.com/templates/slack-channels) (paid, 400 AI credits; core): Why a 30,000-member channel is not a big DM, and why the unread badge is the hardest number to keep.
- [Encrypted delivery - one tick, two ticks, blue](https://tierslate.com/templates/whatsapp-delivery) (paid, 800 AI credits; deep): What changes when the server cannot read the message, and why every tick after the first is a device claim.
- [Webhook delivery - retrying into somebody else's outage](https://tierslate.com/templates/webhook-delivery) (paid, 200 AI credits; starter): Why a webhook is a promise to keep calling until the receiver answers, and how retries avoid becoming an attack.
- [Notification router - one event, the right channel, once](https://tierslate.com/templates/notification-router) (paid, 400 AI credits; core): How one event is turned into email, push or SMS by preferences and quiet hours, without sending it twice.

### Video & media

Upload, transcode, deliver - and pay for the bandwidth.

- [Image CDN - resize on the fly, or store every size](https://tierslate.com/templates/image-cdn) (paid, 200 AI credits; starter): Why the cache key is the design, and why egress and the long tail of misses set the bill, not CPU.
- [Live streaming - latency against the buffer that saves you](https://tierslate.com/templates/live-streaming) (paid, 800 AI credits; deep): Why segment length sets latency, resilience and cost at once, and what each second removed costs.
- [Streaming playback - the bytes were already next to you](https://tierslate.com/templates/netflix-streaming) (paid, 800 AI credits; deep): Why streaming is a bandwidth problem, solved by placing the bytes inside the network before anyone asks.
- [Transcoding pipeline - 480 tasks, one file](https://tierslate.com/templates/video-transcoding) (paid, 400 AI credits; core): Why one number, the size of a segment, sets the cost, latency and failure behaviour of the whole pipeline.
- [Video upload - one file in, seven encodes out](https://tierslate.com/templates/youtube-upload) (paid, 400 AI credits; core): Why a durable receipt for a 500 MB upload and a video that plays everywhere are two separate promises.
- [File upload - the bytes never touch your server](https://tierslate.com/templates/file-upload) (paid, 200 AI credits; starter): How presigned URLs send uploads straight to object storage, and what the server still has to check afterwards.
- [Music streaming - three minutes of audio, played a billion times](https://tierslate.com/templates/music-streaming) (paid, 400 AI credits; core): Why audio is small enough to prefetch, and why play counts and royalties are the hard ledger underneath.
- [Short video feed - the next swipe is already downloading](https://tierslate.com/templates/short-video-feed) (paid, 600 AI credits; deep): Why a short-video feed is ranking plus prefetch, and why the first second of video decides retention and cost.
- [Video calls - forwarding streams, not mixing them](https://tierslate.com/templates/video-conferencing) (paid, 800 AI credits; deep): Why a group call forwards streams through an SFU, and how bandwidth estimation keeps a bad link from ruining the call.

### Marketplaces & booking

Two-sided systems where inventory must not be sold twice.

- [Checkout - holding stock you have not sold yet](https://tierslate.com/templates/amazon-checkout) (paid, 400 AI credits; core): Why stock is held before the card is charged, and what must unwind when the charge fails.
- [Auction bidding - the clock is part of the system](https://tierslate.com/templates/auction-bidding) (paid, 800 AI credits; deep): Why bids are ordered by a sequence under one lock rather than a clock, and how soft close moves the end.
- [Food delivery - three parties and a promise](https://tierslate.com/templates/food-delivery) (paid, 400 AI credits; core): How three parties who can each say no move one order through a shared state machine to a promised ETA.
- [Hotel booking - selling a range, on purpose, slightly twice](https://tierslate.com/templates/hotel-booking) (paid, 400 AI credits; core): Why a stay is sold night by night or not at all, and why selling the last room twice is sometimes deliberate.
- [Seat sales - fifty thousand people, one hundred seats](https://tierslate.com/templates/ticketmaster-seats) (paid, 800 AI credits; deep): Why fifty thousand buyers for one hundred seats is a contention problem that sharding cannot solve.
- [Coupon codes - redeemable once, by anyone, at the same moment](https://tierslate.com/templates/coupon-codes) (paid, 200 AI credits; starter): Why a single-use code is a race between every checkout holding it, and how a conditional write settles it.
- [Rental search - availability is a calendar, not a column](https://tierslate.com/templates/rental-search) (paid, 400 AI credits; core): How a stay search filters by place, dates and price at once, and why the availability calendar is the bottleneck.
- [Job board - search, apply, and the recruiter's inbox](https://tierslate.com/templates/job-board) (paid, 400 AI credits; core): How listings are indexed for search and applications are routed, and why expired jobs must disappear fast.

### Infrastructure primitives

The building blocks an interview asks you to build from scratch.

- [URL shortener - one write, a million reads](https://tierslate.com/templates/url-shortener) (paid, 200 AI credits; starter): Why one tiny write and a hundred cacheable reads make two systems sharing a single table.
- [Distributed cache - the ring, and what a node leaving costs](https://tierslate.com/templates/distributed-cache) (paid, 400 AI credits; core): Why a hash ring moves a sliver of keys when a node leaves, and why the hot key and the miss storm remain.
- [Key-value store - quorums, and where the consistency knob sits](https://tierslate.com/templates/key-value-store) (paid, 800 AI credits; deep): How a key finds its replicas, and why choosing how many to wait for buys overlap rather than order.
- [Rate limiter - token bucket, and where the counter lives](https://tierslate.com/templates/rate-limiter) (free; core): Why the hard part of limiting requests is where the shared counter lives, not the algorithm.
- [Unique ID generator - 64 bits, and two facts nobody can check](https://tierslate.com/templates/unique-id-generator) (paid, 200 AI credits; starter): How 64 bits buy sortable ids with no central counter, and what happens when the clock goes backwards.
- [Web crawler - a frontier, and the trap of crawling forever](https://tierslate.com/templates/web-crawler) (paid, 400 AI credits; core): Why a crawler that feeds on its own output needs politeness, deduplication and loop brakes more than speed.
- [Pastebin - a blob store with a short name](https://tierslate.com/templates/pastebin) (free; starter): Why storing text is the easy part and expiry, abuse and the read path are the design.
- [Load balancer - spreading traffic, and noticing who is dead](https://tierslate.com/templates/load-balancer) (free; starter): How requests are spread across servers, and why the health check matters more than the algorithm.
- [API gateway - one front door for many services](https://tierslate.com/templates/api-gateway) (free; starter): Why auth, routing and limits move to one front door, and what that door costs when it falls over.
- [Login and sessions - who you are, on every request](https://tierslate.com/templates/login-sessions) (paid, 200 AI credits; starter): How a password becomes a session, and what changes when the session is a signed token nobody can revoke.
- [Feature flags - a config change that ships like code](https://tierslate.com/templates/feature-flags) (paid, 200 AI credits; starter): Why a flag is evaluated locally from a pushed ruleset, and what a stale ruleset does during an incident.
- [Secrets manager - the one store everything trusts](https://tierslate.com/templates/secrets-manager) (paid, 200 AI credits; starter): How secrets are encrypted under a key nobody holds directly, and why rotation is the feature, not storage.
- [DNS - the cache that runs the internet](https://tierslate.com/templates/dns-resolver) (paid, 200 AI credits; starter): How a name becomes an address through layers of caches, and why the TTL decides how fast a mistake spreads.
- [Distributed cron - exactly one runner at nine o'clock](https://tierslate.com/templates/cron-scheduler) (paid, 200 AI credits; starter): Why a scheduled job needs a lease so it runs once, not once per server, and what a missed tick should do.
- [Background job queue - at least once, and the retry that doubles it](https://tierslate.com/templates/job-queue) (paid, 400 AI credits; core): Why a job queue delivers at least once, and how idempotent workers and dead letters keep retries honest.
- [Code execution sandbox - running a stranger's program](https://tierslate.com/templates/code-execution-sandbox) (paid, 600 AI credits; deep): How untrusted code is run in isolated, time-limited sandboxes, and why the queue in front of them is the real system.
- [Distributed log - Kafka from the partition up](https://tierslate.com/templates/message-queue) (paid, 800 AI credits; deep): Why an append-only partitioned log gives ordering and replay, and what replication and consumer offsets cost.
- [Consensus - a leader, a log, and a majority](https://tierslate.com/templates/raft-consensus) (paid, 800 AI credits; deep): How Raft keeps replicas agreeing through elections and a replicated log, and what a network partition really does.
- [Object storage - eleven nines from cheap disks](https://tierslate.com/templates/object-storage) (paid, 800 AI credits; deep): How objects are split, erasure-coded and placed across failure domains so losing disks never loses data.

### Payments & ledgers

Systems where losing a write is losing money.

- [Double-entry ledger - the balance is not a column](https://tierslate.com/templates/double-entry-ledger) (paid, 400 AI credits; core): Teaches why money is stored as immutable movements and read as a derived sum, and what it costs to never update a total.
- [Fraud detection - a decision that must fit in 120 milliseconds](https://tierslate.com/templates/fraud-detection) (paid, 800 AI credits; deep): Teaches how a risk decision is split between a synchronous call with a hard deadline and an asynchronous review that is allowed to be right.
- [Payment gateway - what a timeout means when the card may already be charged](https://tierslate.com/templates/payment-gateway) (paid, 400 AI credits; core): Teaches how a payment system stays correct when its authoritative dependency can fail in a way that tells you nothing.
- [Matching engine - price-time priority, and why the clock cannot decide who was first](https://tierslate.com/templates/stock-exchange) (paid, 800 AI credits; deep): Teaches why an exchange assigns order with a sequence number instead of measuring it with a clock, and what a single-threaded book buys in return.
- [Wallet transfers - the state machine, the hold that expires, and the reversal that cannot](https://tierslate.com/templates/wallet-transfers) (paid, 200 AI credits; starter): Teaches how money moves between two accounts in one system without ever being in both places or neither, and what it costs to make every step undoable.
- [OTP verification - six digits and a clock](https://tierslate.com/templates/otp-verification) (paid, 200 AI credits; starter): How a one-time code is issued, rate limited and checked, and why the SMS bill is the attack surface.
- [Subscription billing - the invoice is computed, not typed](https://tierslate.com/templates/subscription-billing) (paid, 400 AI credits; core): How a recurring charge is driven by a billing clock, proration and dunning, and why plan changes are the hard part.
- [Currency exchange - a rate that is only true for a few seconds](https://tierslate.com/templates/currency-exchange) (paid, 400 AI credits; core): Why a quoted FX rate is a short-lived promise with an expiry, and how rounding is a ledger decision.
- [Loyalty points - a currency you print yourself](https://tierslate.com/templates/loyalty-points) (paid, 400 AI credits; core): Why points are a ledger with expiry and liability, and why a balance column is the wrong answer again.

### Data & analytics

Pipelines, metrics and the lag between event and answer.

- [Ad serving - an auction inside a page load](https://tierslate.com/templates/ad-serving) (paid, 800 AI credits; deep): Why a system with eighty milliseconds to decide must spend money it cannot yet count.
- [Analytics pipeline - the lag between an event and the answer](https://tierslate.com/templates/analytics-pipeline) (paid, 400 AI credits; core): Why a click takes ten seconds to reach one dashboard and until tomorrow to reach the one people trust.
- [Log aggregation - the index is bigger than the data](https://tierslate.com/templates/log-aggregation) (paid, 400 AI credits; core): Why searching your logs costs thirteen times more than keeping them, and what you can no longer ask once you sample.
- [Metrics and monitoring - cardinality is the thing that kills you](https://tierslate.com/templates/metrics-monitoring) (paid, 400 AI credits; core): Why one label with unbounded values takes down the system that was supposed to explain the outage.
- [Recommendation engine - retrieve a thousand, rank twenty](https://tierslate.com/templates/recommendation-engine) (paid, 800 AI credits; deep): Why the feed is computed in a hundred milliseconds by a model that is a day out of date.
- [Leaderboard - a sorted set and the rank nobody stores](https://tierslate.com/templates/leaderboard) (free; starter): How a sorted set answers top ten and my rank in milliseconds, and why rank is computed rather than stored.
- [Search autocomplete - an answer before the word is finished](https://tierslate.com/templates/typeahead-autocomplete) (paid, 200 AI credits; starter): Why suggestions come from a precomputed prefix index, and why freshness is traded for speed on every keystroke.
- [View counter - counting a million clicks without a million writes](https://tierslate.com/templates/view-counter) (paid, 200 AI credits; starter): Why a counter on a hot row is batched in memory, and how much of the count you may lose on a crash.
- [Uptime monitor and status page - checking from outside](https://tierslate.com/templates/status-page) (paid, 200 AI credits; starter): Why uptime is measured from many regions outside your network, and why the status page must not share its fate.
- [A/B testing platform - assignment is the easy half](https://tierslate.com/templates/ab-testing) (paid, 400 AI credits; core): How users are bucketed deterministically, and why exposure logging and metric pipelines decide whether a result is real.
- [ETL and the data warehouse - yesterday, correctly](https://tierslate.com/templates/etl-warehouse) (paid, 400 AI credits; core): Why batch loads trade freshness for correctness, and how late data and reruns are made safe.
- [Full-text search - the inverted index and the shard that is slow](https://tierslate.com/templates/full-text-search) (paid, 800 AI credits; deep): How an inverted index answers a query across shards, and why the slowest shard sets every response time.

### Location & logistics

Geospatial indexes, matching and moving things.

- [Fleet tracking - 21,600 writes per vehicle per day](https://tierslate.com/templates/fleet-tracking) (paid, 400 AI credits; core): Teaches how a continuous position firehose is split into a tiny live picture and an enormous history, and how retention rather than hardware decides what it costs.
- [Geofencing - many points against many polygons](https://tierslate.com/templates/geofencing) (paid, 800 AI credits; deep): Teaches how a covering index reduces every-point-against-every-fence to a handful of tests, and why a jittery GPS makes the crossing itself the harder problem.
- [Maps routing - precompute, then watch it go stale](https://tierslate.com/templates/maps-routing) (paid, 800 AI credits; deep): Teaches how a shortest path over a continental road graph is bought with precomputation, and what live traffic does to work that was done last night.
- [Proximity search - the index is the design](https://tierslate.com/templates/proximity-search) (paid, 200 AI credits; starter): Teaches how to size a geospatial index against the query it serves, and why the nearest answer is usually in the cell next door.
- [Ride matching - the nearest car is the wrong car](https://tierslate.com/templates/ride-matching) (free; core): Teaches how a geospatial index turns supply and demand into a dispatch decision, and why that decision is an assignment over a batch rather than a nearest-neighbour lookup.
- [Parking reservation - a spot is a time slot with a location](https://tierslate.com/templates/parking-reservation) (paid, 400 AI credits; core): How spots are booked by time window without double booking, and what happens when a car overstays.
- [Package tracking - scan events and the promised date](https://tierslate.com/templates/package-tracking) (paid, 400 AI credits; core): How carrier scan events become one shipment timeline, and why events arrive late and out of order.
- [Surge pricing - a price set by a map that changes every minute](https://tierslate.com/templates/surge-pricing) (paid, 600 AI credits; deep): How supply and demand per map cell set a multiplier, and why the price must be locked when it is shown.

### Collaboration

Several people editing one thing without losing an edit.

- [Calendar scheduling - a time that suits five people](https://tierslate.com/templates/calendar-scheduling) (paid, 400 AI credits; core): Why a meeting time is computed from rules and guesses rather than read from a table, and what that costs.
- [Code review - the comment is on a line that moved](https://tierslate.com/templates/code-review) (paid, 400 AI credits; core): What it takes to keep a conversation attached to code that is rewritten underneath it while the conversation is still going.
- [Collaborative editor - two carets in one paragraph](https://tierslate.com/templates/collaborative-editor) (paid, 600 AI credits; deep): How two people type into one document at the same time without either of them losing a character.
- [Version control - the commit graph is a DAG](https://tierslate.com/templates/version-control) (paid, 800 AI credits; deep): Why history is a graph rather than a list, and what that costs at merge, at fetch and at garbage collection.
- [Whiteboard sync - the cursors cost more than the drawing](https://tierslate.com/templates/whiteboard-sync) (paid, 400 AI credits; core): Why a shared canvas is mostly a broadcast problem, and what happens to a shape that two people grab at once.
- [Kanban board - ordering cards without renumbering them](https://tierslate.com/templates/kanban-board) (paid, 400 AI credits; core): How cards are reordered with fractional ranks instead of renumbering, and how live updates reach every viewer.
- [File sync - every laptop is a replica](https://tierslate.com/templates/file-sync) (paid, 600 AI credits; deep): How files sync across devices by chunk and version, and what a conflict looks like when two laptops were offline.
- [Multiplayer game server - the server decides what happened](https://tierslate.com/templates/multiplayer-game) (paid, 800 AI credits; deep): Why an authoritative server with client prediction hides latency, and how a tick rate sets cost and fairness.

### Database schemas

Entity boards that Generate SQL turns into real DDL.

- [E-commerce orders](https://tierslate.com/templates/ecommerce-schema) (paid, 400 AI credits; core): Orders, line items and the price that must not change after checkout.
- [Multi tenant SaaS](https://tierslate.com/templates/saas-multitenant-schema) (paid, 600 AI credits; deep): Tenant isolation, and every join that could leak across it.
- [Learning platform](https://tierslate.com/templates/lms-schema) (paid, 400 AI credits; core): Courses, lessons, enrolments and the progress that must survive a course being edited.
- [Warehouse inventory](https://tierslate.com/templates/inventory-schema) (paid, 400 AI credits; core): Stock by location, movements as rows, and why on-hand is a sum rather than a field.

### AI & LLM systems

Retrieval, model serving and the GPU that sets the bill.

- [RAG chatbot - the answer is only as good as the retrieval](https://tierslate.com/templates/rag-chatbot) (paid, 400 AI credits; core): Why a document chatbot is a search system feeding a model, and how chunking and citations decide trust.
- [LLM gateway - one API in front of every model provider](https://tierslate.com/templates/llm-gateway) (paid, 400 AI credits; core): How prompts are routed, cached, metered and failed over across providers, and why tokens are the unit of cost.
- [Vector search - nearest neighbours, approximately](https://tierslate.com/templates/vector-search) (paid, 600 AI credits; deep): Why similarity search uses an approximate index that trades recall for speed, and how filters break it.
- [LLM inference serving - the GPU is the bill](https://tierslate.com/templates/llm-inference-serving) (paid, 800 AI credits; deep): How batching, KV cache and streaming turn a scarce GPU into many conversations, and why latency fights throughput.

## Mockups

22 example UI mockups, each a complete board of several screens drawn with the mockup components - apps and websites a designer or engineer can open, edit and turn into React code. All are free to open on every plan; copying or downloading the generated React code is part of Pro.

- [Food delivery app](https://tierslate.com/mockups/food-delivery-app) (mobile, 4 screens): Browse restaurants, pick dishes, check out and follow the courier - four mobile screens.
- [Shopping website](https://tierslate.com/mockups/shopping-website) (web, 4 screens): An online clothing store - home page, product listing with filters, product detail and checkout.
- [Banking app](https://tierslate.com/mockups/banking-app) (mobile, 3 screens): A mobile bank - balance with quick actions and recent activity, a transaction detail and a send-money flow.
- [Admin dashboard](https://tierslate.com/mockups/admin-dashboard) (web, 2 screens): A store back office - KPI cards, revenue chart, top products and recent orders, plus a customer profile page.
- [Social feed](https://tierslate.com/mockups/social-feed) (mobile, 3 screens): A photo-sharing app - stories and a post feed, a new-post composer and a profile with stats and a photo grid.
- [Travel booking](https://tierslate.com/mockups/travel-booking) (web, 3 screens): A hotel booking site: search with dates and guests, filtered results with hotel cards, and a guest details + payment checkout.
- [SaaS landing page](https://tierslate.com/mockups/saas-landing-page) (web, 1 screen): A full marketing page for a project-management product: hero with two calls to action, features, pricing tiers, a testimonial, FAQ and footer.
- [Chat messenger](https://tierslate.com/mockups/chat-messenger) (desktop, 2 screens): A desktop messaging app: conversation list with unread badges, a group thread with message bubbles and attachments, and a notifications settings dialog.
- [Music player](https://tierslate.com/mockups/music-player) (mobile, 2 screens): A mobile music app: a library with playlists and recently played tracks, and a now-playing screen with album art, progress and playback controls.
- [Sign in and sign up flows](https://tierslate.com/mockups/auth-flows) (web, 3 screens): The three account screens every product needs: sign in with social options, create an account with a password strength meter, and reset a forgotten password.
- [iOS fitness app](https://tierslate.com/mockups/ios-fitness-app) (mobile, 5 screens): An iPhone activity tracker in the iOS 17/18 look: large-title navigation, activity rings, widgets, inset grouped lists, a tab bar, a settings sheet, an action sheet and an alert over the keyboard.
- [Android mail app](https://tierslate.com/mockups/android-mail-app) (mobile, 6 screens): A Material 3 (Material You) email client: search bar, filter chips, inbox list, FAB, navigation drawer, message view, compose with a dialog, a schedule-send bottom sheet, and a tablet layout with a navigation rail and date/time pickers.
- [Ride hailing app](https://tierslate.com/mockups/ride-hailing-app) (mobile, 3 screens): A mobile ride app: pick up and destination over a map, a choice of ride types with prices, and a live driver-on-the-way screen.
- [Video streaming site](https://tierslate.com/mockups/video-streaming-site) (web, 3 screens): A streaming service - browse rows with continue watching and trending titles, a series detail page with episodes, and the video player.
- [Project board](https://tierslate.com/mockups/project-board) (web, 2 screens): A kanban project tool - columns of task cards with tags, progress and assignees, and a task detail page with subtasks, activity and properties.
- [Calendar app](https://tierslate.com/mockups/calendar-app) (desktop, 3 screens): A desktop calendar - a colour-coded week view with a mini month and calendar toggles, an event editor with guests, and a month view with an agenda.
- [Real estate listings](https://tierslate.com/mockups/real-estate-listings) (web, 2 screens): A home search site - filters, listing cards beside a map, and a listing page with a photo gallery, key facts and a tour request form.
- [Recipe app](https://tierslate.com/mockups/recipe-app) (mobile, 3 screens): A mobile cooking app: discover recipes by category, a recipe page with ingredients and servings, and a step-by-step cooking mode with a timer.
- [CRM dashboard](https://tierslate.com/mockups/crm-dashboard) (web, 2 screens): A sales CRM: a pipeline board with KPIs and deal cards per stage, and a contact page with the open deal, activity timeline, tasks and call logging.
- [Onboarding flow](https://tierslate.com/mockups/onboarding-flow) (mobile, 3 screens): A mobile app’s first-run flow: a welcome screen, a permissions step with toggles and a notification preview, and a profile setup form.
- [Note-taking app](https://tierslate.com/mockups/note-taking-app) (desktop, 2 screens): A desktop notes app: notebooks and tags in a sidebar, a note list, a rich editor with checklist and table, and a share dialog with access controls.
- [Smart home app](https://tierslate.com/mockups/smart-home-app) (mobile, 3 screens): A mobile smart home controller: rooms at a glance with scenes and a door lock, a room screen with light and device controls, and a thermostat with schedule.

## Not here

- `/api/` is the application's own server routes. They answer 401 to anything unauthenticated and contain no content.
- `/collab` is a websocket upgrade path, not a page.
- Individual boards are private and are not addressable by any URL a server sees.
- `https://tierslate.com/cart` exists and is public, but it is one reader's own cart and is empty for anybody else. It is `noindex` and is deliberately absent from the sitemap; there is nothing there to cite.

Sitemap: https://tierslate.com/sitemap.xml