Build: Slack-like Messaging App
Toggle features and choose options to customize your spec
Preset
Authentication Methods*
Access Control*
Multi-factor Authentication
Tradeoffs
Each provider requires an OAuth app registration and key rotation policy
Requires IdP partnership and XML-based protocol handling; significant integration work
Permission checks must be applied consistently across every data access path
Conversation Types*
Message History*
Rich Content
Tradeoffs
Message routing logic grows significantly; fan-out to members must be handled carefully
Storage costs grow unbounded; requires indexing strategy for search
Requires object storage (S3/R2) and content moderation policy
Server must fetch external URLs on behalf of users; adds latency and SSRF risk
Delivery Method*
User Control
Tradeoffs
Requires persistent connection infrastructure (e.g. Redis pub/sub, WebSocket server)
Higher server request volume; notifications may lag by poll interval
Requires APNs/FCM credentials and certificate management
Significantly more complex preference storage and UI
Search Approach*
Search Scope*
Tradeoffs
Requires FTS index maintenance; adds write-time overhead
Embedding generation adds latency and API cost per indexed document
Results must be unified and ranked across disparate data models
Storage Backend*
File Processing
Tradeoffs
Not horizontally scalable; lost on server replacement without backup
Higher monthly cost; requires cache invalidation strategy
Upload latency increases; requires AV service integration
Authorization Model*
Permission Scope*
Custom Role Management
Tradeoffs
Fast to build but every 'special case' access rule becomes bespoke code that's hard to audit
Requires a policy engine and relationship store kept in sync with primary data
Every list/read query must filter by ACL — expect query-plan work and caching investment
Support load increases substantially — each customer now has a unique permission configuration
Rate Limit Algorithm*
What to Limit By*
Abuse Prevention Layer
Response Behavior*
Tradeoffs
False positives behind corporate NATs; attackers bypass with rotating proxies
Noisy-neighbor protection — one tenant cannot starve others
Allows bursts but requires a per-identity bucket state in Redis — higher memory footprint
Meaningful latency cost at the edge if the WAF is geographically distant from users
Onboarding Format*
Personalization Signals
Activation Support
Tradeoffs
Controls first-experience but introduces sign-up drop-off proportional to wizard length
Requires event tracking + scheduled jobs + segmentation infrastructure
Staffing cost scales with signup volume — not viable for self-serve products below a certain ACV
Summary
8 of 9 features enabled
Commonly added together
Gap analysis
Most communication apps include Audit Logging
Effort Estimate
10+ weeks
8 enabled features
Key Decisions
User System & Auth
Will this product be sold to businesses (B2B)?
If yes
Add SAML/SSO and RBAC. Enterprise procurement often requires both.
If no
Email + password plus one OAuth option covers 95% of consumer use cases.
User System & Auth
Is this a security-sensitive application?
If yes
Enable TOTP MFA. Consider making it mandatory for privileged users.
If no
MFA is optional — offer it but do not require it to reduce friction.
User System & Auth
Email+password, passwordless, or SSO-only?
If yes
Passwordless (magic links or passkeys) eliminates password reset tickets and credential stuffing risk.
If no
Keep email+password as a universal fallback — OAuth outages should not lock users out.
User System & Auth
Do you need social providers (Google, GitHub, Apple)?
If yes
Add Google for B2C breadth; add GitHub for developer tools; add Apple only if you ship iOS (App Store requires it when you offer other social login).
If no
Skip social OAuth and avoid the app registration / key rotation overhead.
User System & Auth
Do you need SCIM provisioning?
If yes
Add SCIM alongside SAML — enterprise IT uses it to auto-provision/deprovision employees and map group membership to roles.
If no
Manual invite flows are fine until your first enterprise customer asks for SCIM in a security review.
User System & Auth
Should MFA be required, optional, or risk-based?
If yes
Risk-based (step up MFA on new device, new IP, or sensitive actions) gives security without friction on every login.
If no
Offer MFA as optional first; require it only for admins or on privileged actions.
User System & Auth
Which MFA factors will you support (TOTP, SMS, WebAuthn/passkeys, hardware keys)?
If yes
Prefer WebAuthn/passkeys and TOTP. Avoid SMS as a primary factor — SIM swapping is a real threat.
If no
TOTP alone (Google Authenticator, Authy) covers the vast majority of users with minimal implementation cost.
User System & Auth
Do you need device fingerprinting or trusted-device flows?
If yes
Remember trusted devices for 30 days to skip MFA; challenge on new device or changed fingerprint.
If no
Re-prompt MFA on every login — simpler and safer for low-volume or highly sensitive apps.
User System & Auth
Offer passkey-only sign-in?
If yes
Passkeys eliminate passwords entirely — use WebAuthn with platform authenticators. Still keep an email recovery path for lost devices.
If no
Offer passkeys as an optional second factor; users without compatible devices keep using passwords.
User System & Auth
Support staff impersonation of user accounts?
If yes
Add an impersonation flow that logs both the staff identity and the target user, with a visible banner in the impersonated session.
If no
Skip impersonation — instead build admin-side read views and support tooling that do not require acting as the user.
User System & Auth
Captcha or bot detection on signup?
If yes
Add hCaptcha or Cloudflare Turnstile on signup and password reset — invisible challenges avoid user friction.
If no
Skip captcha for internal tools or invite-only products where bot signups are not a realistic threat.
User System & Auth
Use lockout or rate-limit throttling for credential stuffing?
If yes
Exponential rate limits per IP and per account — lockouts create support tickets and denial-of-service vectors via targeted lockout.
If no
If account takeover risk is low, a simple fixed rate limit (e.g., 10 attempts per 15 min) is sufficient.
User System & Auth
Allow multiple concurrent sessions per user?
If yes
Show active sessions in account settings with a revoke button — expected behavior for any multi-device product.
If no
Single-session apps (banking, compliance) should terminate old sessions on new login.
Messaging
Do users need to communicate in groups beyond 1:1?
If yes
Add channels. Start with just public channels; add private later.
If no
Direct messages only is much simpler to implement and moderate.
Messaging
Is message history a compliance or product requirement?
If yes
Use full history. Plan your archiving and retention policy up front.
If no
Limited history or ephemeral reduces storage cost and GDPR surface.
Messaging
Is synchronous real-time required, or is async acceptable?
If yes
Real-time via WebSocket or SSE — users expect sub-second delivery in chat. Budget for pub/sub fan-out infrastructure.
If no
Async messaging (poll-on-open, email-style) is dramatically simpler and fine for inbox-style products.
Messaging
Support threaded replies off a specific message?
If yes
Add a parent_message_id column; surface threads as a side-panel to avoid polluting the main channel stream.
If no
Flat channels are simpler — users can quote-reply to fake threading.
Messaging
Show typing indicators?
If yes
Broadcast ephemeral "user is typing" events over the same WebSocket/pub-sub channel — do not persist them.
If no
Skip typing indicators for async or low-volume chat; they add connection chatter without proportional value.
Messaging
Show read receipts?
If yes
Track a per-user last_read_message_id per conversation; update on message view. Expect user pushback on privacy — make it opt-out per user.
If no
Skip read receipts for privacy-forward or async products — they create social pressure users often dislike.
Messaging
End-to-end encryption required?
If yes
Use Signal protocol or MLS — but E2EE kills server-side search, moderation, and link preview. Accept those tradeoffs explicitly.
If no
TLS in transit plus encryption at rest is the standard baseline for business messaging.
Messaging
Voice or video calls in addition to text?
If yes
Use a third-party (Daily, Twilio, LiveKit) — building WebRTC infra from scratch is a multi-quarter project.
If no
Text-only keeps you focused. Add calls via embedded providers only when users are actively requesting them.
Messaging
File and media sharing within messages?
If yes
Wire in object storage and content-type validation; virus-scan uploads in public spaces. Presigned URLs for direct upload.
If no
Text-only messaging sidesteps storage, moderation, and security burden entirely.
Messaging
Full-text search over messages?
If yes
Postgres tsvector or SQLite FTS5 up to ~10M messages; dedicated engine (Meilisearch, Typesense) beyond that.
If no
Skip search in ephemeral or short-history products — there is nothing worth indexing.
Messaging
Allow edit and delete after send?
If yes
Show an edited marker; tombstone deletes in threaded views to preserve reply context. Audit-log edits for compliance.
If no
Immutable messages are correct for audit-sensitive contexts (finance, legal, regulated chat).
Messaging
Queue messages sent while offline for later delivery?
If yes
Client-side outbox plus server-side reconciliation on reconnect — essential for mobile and spotty-network users.
If no
Fail-fast (error on send if offline) is simpler but poor UX on mobile.
Messaging
Emoji reactions on messages?
If yes
Simple join table (message, user, emoji) — cuts reply noise dramatically and is a cheap engagement feature.
If no
Skip if your product is async-only or formal (compliance chat) where casual reactions add nothing.
Messaging
Reactions on thread-level (not just individual messages)?
If yes
Support reactions on thread parents as first-class — useful in collaboration tools where teams converge on a decision.
If no
Message-level reactions only keep the data model simpler.
Messaging
Push-to-device notifications for new messages?
If yes
Integrate APNs and FCM. Batch notifications to avoid flooding — one push per channel per minute, not per message.
If no
Skip push for web-only products; in-app badges plus email digests cover the re-engagement need.
Messaging
Per-message delivery confirmation (sent/delivered/read)?
If yes
Track three states per recipient — storage grows quickly (N states × M recipients per message). Expensive on large channels.
If no
Single "sent" state is enough for most chat products. Add granularity only when users ask.
Notifications
Do users need to know about events immediately?
If yes
Use real-time delivery. Budget for WebSocket/SSE infrastructure.
If no
Polling is simpler and cheaper — pick an interval that matches your SLA.
Notifications
Is this a mobile-first product?
If yes
Add mobile push (APNs/FCM). Plan for certificate rotation.
If no
Skip mobile push; web notifications or email cover most cases.
Notifications
Do users often go offline and still need to receive notifications?
If yes
Add email fallback driven by a "last seen" timestamp. Send email only when the user has been offline >5 minutes to avoid spam.
If no
In-app real-time or polling is enough — email adds unsubscribe risk without upside.
Notifications
Will you send multiple notification types with different urgency levels?
If yes
Adopt per-type granularity so users can mute digests without muting security alerts. Define the taxonomy up front.
If no
A single all-or-nothing toggle is enough and avoids preference-UI bloat.
Notifications
Is notification volume high enough that users will complain about floods?
If yes
Batch similar notifications in a rolling window (e.g., "Alice and 12 others liked your post"). Entity + time-window grouping is the standard pattern.
If no
Deliver individually — grouping adds UI complexity that is not worth it at low volume.
Notifications
Are any notifications security-critical or financially sensitive?
If yes
Require at-least-once delivery with persistent storage and retry. Pair with email fallback for the highest-urgency classes.
If no
Best-effort (fire-and-forget) is fine for social and informational notifications.
Notifications
Do users have reasonable expectations of quiet hours / do-not-disturb?
If yes
Add a per-user quiet-hours window and a priority flag that lets critical alerts bypass it. Requires per-type granularity to know what is critical.
If no
Skip quiet hours — the added preference surface is not worth it for low-volume products.
Notifications
Do users need to mark notifications as read / track what they have seen?
If yes
Persist notifications with a read state. Consider cross-device read-state sync via a server-side timestamp or event log.
If no
Ephemeral toast-style notifications are simpler and appropriate for low-stakes alerts.
Notifications
Do you need delivery analytics (delivered, opened, clicked)?
If yes
Use a provider like Knock or Novu that tracks delivery funnel by channel. Essential if notifications drive revenue or retention KPIs.
If no
Skip the instrumentation — simple success/failure logs are enough.
Notifications
Do users have multiple devices (web + mobile + desktop)?
If yes
Sync read-state across devices via a server-side last-read timestamp. Without this, users see the same notification over and over.
If no
Device-local read state is simpler and avoids backend round-trips.
Notifications
Do you need SMS as a notification channel?
If yes
Use Twilio or Messagebird. Reserve SMS for high-priority alerts only — it is expensive per message and users churn fast on SMS spam.
If no
Skip SMS — push and email cover 99% of use cases at a fraction of the cost.
Notifications
Are some notifications purely in-app / ephemeral (toast-style)?
If yes
Deliver via SSE/WebSocket without persisting — no storage, no retry, no read-state UI. Good for "Saved", "Uploaded" feedback.
If no
All notifications go through the durable pipeline with read-state tracking.
Notifications
Do you need localized notification content (multi-language)?
If yes
Store notification templates with i18n keys and render per-recipient locale at send time. Avoid pre-rendered strings in the event.
If no
Hardcoded English strings are fine until you have non-English users.
Notifications
Do you have more than 5 notification types or expect to add more regularly?
If yes
Invest in a template engine (Knock, MJML, or Handlebars) with versioned templates rather than hardcoded message strings.
If no
Hardcoded message strings in the sender are simpler and fine for a small stable set.
Notifications
Do product/marketing teams need to preview and test-send notifications before release?
If yes
Build an internal preview tool with a test-recipient flag. Prevents production embarrassments.
If no
Skip — engineers can validate in staging until non-engineers start authoring templates.
Notifications
Are there urgent notifications that must bypass quiet hours (security alerts, outages)?
If yes
Add a priority flag on notifications and skip DND for priority=urgent. Document this behavior so users expect it.
If no
Quiet hours apply uniformly — simpler and avoids abuse of the override.
Search
Do users search by meaning, not just keywords?
If yes
Invest in semantic/vector search. Start with full-text and migrate.
If no
Full-text search covers keyword use cases at a fraction of the cost.
Search
DB full-text or a dedicated engine (Elasticsearch, Typesense, Algolia)?
If yes
Reach for a dedicated engine when DB FTS can't meet latency or ranking needs. Algolia for hosted DX, Typesense/Meilisearch for self-hosted.
If no
Start with SQLite FTS5 or Postgres tsvector — no extra service to run.
Search
Do users need faceted filtering (refine by category, tag, date range)?
If yes
Use a dedicated engine — faceting across millions of rows in Postgres FTS gets slow fast. Typesense and Algolia do this natively.
If no
Keyword-only over FTS is sufficient; add facets later.
Search
Do you need typo tolerance / fuzzy matching on short queries?
If yes
A dedicated engine (Typesense, Algolia, Meilisearch) gives this out of the box. DB FTS typo tolerance is weak.
If no
Strict matching is fine for structured queries and technical users.
Search
Will you support multiple languages with proper stemming?
If yes
Pick an engine with per-locale analyzers (Elasticsearch, Meilisearch). Postgres tsvector ships only a handful of language dictionaries.
If no
English-only tsvector or FTS5 is plenty.
Search
Do users expect personalized ranking (their clicks influence their results)?
If yes
Algolia or a custom scoring layer on top of an engine — personalization needs per-user signals, not just index weights.
If no
Use global relevance scoring (BM25) — simpler and predictable.
Search
Is autocomplete / instant search (as-you-type) part of the UX?
If yes
Pick Typesense, Algolia, or Meilisearch — all tuned for sub-50ms responses. Postgres FTS will feel sluggish here.
If no
Submit-driven search works against any backend.
Search
Do you need search analytics (popular queries, zero-result queries)?
If yes
Log queries + result counts separately; feed into your analytics pipeline. Algolia and Meilisearch expose this natively.
If no
Skip until product teams ask for it.
Search
Must results respect per-user permissions (ACL-aware)?
If yes
Index ACL identifiers alongside documents and filter at query time. Global cross-entity search is especially risky — validate before shipping.
If no
A flat index is simpler; use when all users see the same corpus.
Search
Do customers need custom synonyms and stop-words (domain vocabulary)?
If yes
A dedicated engine with synonym dictionaries (Algolia, Elasticsearch) — editable without re-indexing.
If no
Default analyzers work for general-purpose text.
Search
Do you need rule-based boosting (featured or sponsored results)?
If yes
Algolia has a dashboard for this; Elasticsearch supports function_score. Don't hand-roll on top of tsvector.
If no
Pure relevance ranking is cleaner.
Search
Is mobile bandwidth a constraint for search-as-you-type?
If yes
Debounce aggressively (~300ms), return tiny payloads, and consider a provider that supports partial-result responses.
If no
Desktop-grade instant search is fine; no special tuning needed.
Search
Must newly created content be searchable within seconds (near-real-time)?
If yes
Index on write into an engine with NRT support (Elasticsearch, Typesense). Budget for higher write amplification.
If no
Batch reindex every few minutes via background job — simpler and cheaper.
Search
Do users search across multiple indices / entity types in one query (federated)?
If yes
Global scope is required. Use Algolia multi-index search or aggregate in app code — plan ranking carefully.
If no
Per-resource search is simpler and faster.
Search
Do users need "did you mean" spell correction for empty-result queries?
If yes
Meilisearch and Algolia provide this out of the box. Ties naturally with zero-result analytics.
If no
Show filters and suggested queries instead; simpler to build.
Search
Should users be able to save searches or get alerts on new matches?
If yes
Store the query, schedule a job to re-run it, and diff results. Pair with the notifications module for delivery.
If no
Manual re-runs cover most use cases; skip the infra.
File Storage
Will the app run on more than one server?
If yes
Object storage is required — local disk breaks horizontal scaling.
If no
Local disk works for prototypes; switch to S3-compatible before scaling.
File Storage
Do users upload files directly via presigned URLs?
If yes
Issue short-lived (5–15 min) presigned PUT URLs so uploads skip your server — cheaper, faster, and sidesteps body-size limits.
If no
Proxying uploads through your API is simpler but caps throughput at your server bandwidth — fine for small files only.
File Storage
Do you need chunked/multipart uploads for large files?
If yes
Use S3 multipart upload for anything over ~100MB — single-PUT uploads fail expensively on flaky networks.
If no
For small files (photos, documents under 10MB), a single PUT is simpler and sufficient.
File Storage
Resumable uploads required?
If yes
Use tus.io protocol or S3 multipart with client-side state so users can resume after network drops — critical for mobile video uploads.
If no
Small-file workflows can safely require restart-on-failure.
File Storage
Auto image/video transcoding or thumbnail generation?
If yes
Pipe uploads to a transcoding service (Cloudinary, Mux, Lambda@Edge with sharp/ffmpeg) — async, never block upload completion.
If no
Skip transcoding for document-heavy workflows where files are not consumed as media.
File Storage
Access model: files public, private, or signed-URL access?
If yes
Private by default with short-lived signed URLs issued per authenticated request — safest for user-generated content.
If no
Fully public buckets are fine for static assets (logos, public images); never for user data.
File Storage
Do you need client-side encryption at rest?
If yes
Encrypt on the client before upload with customer-managed keys — required for strict compliance (healthcare, legal).
If no
Server-side encryption (SSE-S3, SSE-KMS) is enough for most workloads and is transparent to clients.
File Storage
Store file metadata in DB or only in object storage?
If yes
Keep a files table in your DB with upload metadata, owner, status, and a content hash — drives permissions and search.
If no
Object storage alone is sufficient only for truly anonymous, throwaway uploads.
File Storage
Do you need cold-storage tiering for old files?
If yes
Use S3 Intelligent-Tiering or lifecycle rules to move files untouched for 30/90 days to Glacier — dramatic cost savings on archival data.
If no
Skip tiering for small storage footprints or hot-access workloads where retrieval latency matters.
File Storage
Track storage usage per user/tenant for quotas/billing?
If yes
Aggregate usage in a separate table, updated on upload/delete events — do not scan object storage for totals in real time.
If no
Skip metering for internal tools or flat-rate products without storage-based billing.
File Storage
CDN fronting for downloads?
If yes
Put Cloudflare or CloudFront in front of downloads — cuts global latency 5–10x and offloads bandwidth cost. Use signed CDN URLs for private content.
If no
Direct object-storage serving is fine when users are regional and file access is infrequent.
File Storage
Deduplicate identical uploads (content-addressed)?
If yes
Hash files on upload and store by content hash — saves storage on duplicate assets but complicates deletion (reference counting).
If no
Skip dedup for user-facing products where each upload is semantically distinct regardless of bytes.
File Storage
Strip EXIF/metadata from uploaded images for privacy?
If yes
Strip GPS and camera metadata on upload — critical for public-facing photos where location leakage is a real privacy risk.
If no
Keep EXIF for creative-workflow tools (photography, mapping) where metadata is a feature, not a leak.
File Storage
Retain prior versions of files (file versioning)?
If yes
Enable S3 object versioning and track versions in your files table — required for collaborative document editing and compliance workflows.
If no
Overwrite-in-place is simpler and sufficient for user-managed assets where history is not valuable.
File Storage
Soft-delete with trash/recycle bin?
If yes
Mark files deleted in DB but retain objects for 30 days — dramatically reduces "help, I lost my file" support tickets.
If no
Hard delete is appropriate for compliance-driven retention where files must be gone when requested.
Roles & Permissions
Do users need different levels of access in different parts of the product?
If yes
Move beyond simple roles — at minimum, adopt RBAC.
If no
A two-value role enum on the user table is plenty.
Roles & Permissions
Do users share individual items (documents, projects) with specific other users?
If yes
You need per-resource scope. Plan for ABAC or ReBAC now, not later.
If no
Workspace-level scope is usually sufficient.
Roles & Permissions
Are enterprise customers asking to configure roles themselves?
If yes
Expose a role editor on the built-in permission primitives; price it.
If no
Ship a fixed role set and iterate based on feedback.
Roles & Permissions
Do you need per-field permission granularity?
If yes
Move to ABAC or a policy engine (OpenFGA, Cerbos) — field-level rules are unmaintainable in RBAC.
If no
Row/resource-level checks are enough; keep the model coarse.
Roles & Permissions
Do permissions need to inherit via hierarchical groups (folder → subfolder, org → team)?
If yes
ReBAC is the natural fit — Zanzibar-style graph traversal handles inheritance cleanly.
If no
Flat role-to-resource assignments are simpler and easier to debug.
Roles & Permissions
Is deny-by-default the required posture?
If yes
Default every permission check to false; require an explicit grant. Standard for compliance-regulated products.
If no
Allow-by-default with blocklist rules is risky — only acceptable for internal tools.
Roles & Permissions
Must users delegate access (X grants Y access to Z) without an admin?
If yes
Per-resource scope is required. Build a share action with grantor tracking in the audit log.
If no
Admin-mediated grants keep the authorization surface auditable and small.
Roles & Permissions
Do you need policy-as-code (OPA, Cedar) managed alongside application code?
If yes
Adopt a policy engine — policies get versioned, reviewed, and tested like any source file.
If no
Keep authorization as a central module in app code until policy churn justifies the engine.
Roles & Permissions
Do grants need to expire automatically (temporary access, contractor windows)?
If yes
Add an expires_at on every grant and a scheduled job that revokes on expiry. Critical for least-privilege compliance.
If no
Permanent grants with manual revocation are simpler but audit-unfriendly.
Roles & Permissions
Do you need a break-glass / super-admin role for incident response?
If yes
Define it explicitly, require MFA to assume it, and audit-log every action taken under it. Keep the member list tiny.
If no
Regular admin + vendor support access covers most cases; avoid god-mode accounts.
Roles & Permissions
Are sensitive role grants (e.g. billing-admin) subject to approval workflow?
If yes
Build a request + approve flow with a second approver on the granting side. Common in SOC 2 environments.
If no
Direct admin grants are faster — add audit logging instead.
Roles & Permissions
Do enterprise customers need SCIM-driven group membership from their IdP?
If yes
Map SCIM groups to roles; treat the IdP as source of truth and avoid manual role edits for SCIM-managed users.
If no
In-app role management is simpler for SMB customers.
Roles & Permissions
Do permission changes need a dedicated audit log (separate from general audit log)?
If yes
Emit a specialized authz-change stream — compliance reviewers need to query grants without sifting through all activity.
If no
Fold permission changes into the general audit log; tag them for easy filtering.
Roles & Permissions
Do API keys need permissions separate from the user who minted them?
If yes
Give keys their own scoped permission set (typically a subset of the user's). Prevents accidental privilege inheritance.
If no
Mirror the minting user's permissions — simpler but revoking a user breaks their keys.
Roles & Permissions
Can you push authorization into the database with row-level security?
If yes
Postgres RLS (or Supabase) centralizes enforcement at the data layer — out-of-band queries can't bypass it. Set auth context on every connection.
If no
Central policy module in app code is easier to debug and port across databases.
Roles & Permissions
Are permission checks on your hot path (every list render)?
If yes
Cache lookups with a short TTL (30–60s) plus a revocation list checked per request — pure DB lookups will bottleneck.
If no
Uncached checks are fine; add caching only when profiler data demands it.
Rate Limiting & Abuse Prevention
Do you have unauthenticated endpoints (signup, login, public API)?
If yes
Add per-IP limits on those endpoints plus CAPTCHA on threshold. Assume credential-stuffing is attempted on day one.
If no
Per-user limits on authenticated APIs are sufficient.
Rate Limiting & Abuse Prevention
Do different customer tiers pay for different rate limits?
If yes
Keyed-on-API-key limits with plan-configured thresholds; expose a usage endpoint.
If no
A single default limit keeps configuration simple.
Rate Limiting & Abuse Prevention
Do you expect adversarial traffic (credential stuffing, scraping, spam)?
If yes
Use sliding window or token bucket — fixed window leaks under boundary timing attacks. Pair with WAF and bot detection.
If no
Fixed-window with Redis INCR + EXPIRE is cheap, simple, and sufficient.
Rate Limiting & Abuse Prevention
Do you have legitimate burst patterns (batch imports, bulk API calls)?
If yes
Token bucket is the right model — allows bursts while enforcing a sustained rate. The standard for commercial API gateways.
If no
Sliding window is simpler and has lower memory overhead.
Rate Limiting & Abuse Prevention
Do you run multiple server nodes behind a load balancer?
If yes
Use centralized Redis for rate-limit state (Upstash Ratelimit, redis-cell). Per-node local counters let attackers get N×limit by rotating through nodes.
If no
In-process counters are fine for single-node deployments and dramatically cheaper.
Rate Limiting & Abuse Prevention
Should users get a warning before they hit a hard limit?
If yes
Emit soft-limit warnings via response headers (X-RateLimit-Remaining) and optionally an in-app notification when usage >80%. Prevents angry support tickets.
If no
Silent throttling at the hard limit is simpler but worse UX — only acceptable for internal APIs.
Rate Limiting & Abuse Prevention
Do you have enterprise customers who negotiate custom limits?
If yes
Build an admin override table keyed on tenant/API-key. Do not hardcode limits — operations team will need to raise them without deploys.
If no
Static per-tier limits in config are simpler and easier to reason about.
Rate Limiting & Abuse Prevention
Can a single user enqueue unbounded background jobs (imports, scrapes, AI calls)?
If yes
Rate-limit the enqueue side separately from the API side. Prevents queue-flooding attacks that bypass request-layer limits.
If no
API-layer limits are sufficient; background jobs are produced by your own code only.
Rate Limiting & Abuse Prevention
Do you have legitimate short bursts you want to allow (e.g. pagination fan-out)?
If yes
Use token bucket with a burst allowance (bucket size > refill rate). Clients can consume the bucket quickly, then settle.
If no
A flat rate is simpler — bursts are a policy decision, not a default.
Rate Limiting & Abuse Prevention
Are you exposed to L3/L4 DDoS (public API, unauthenticated endpoints)?
If yes
Put Cloudflare, AWS Shield, or Fastly in front of your origin. Application-layer rate limiting cannot absorb network-layer floods.
If no
Application-layer limits are sufficient for authenticated-only APIs.
Rate Limiting & Abuse Prevention
Do some endpoints cost 100x more than others (AI calls, complex queries, exports)?
If yes
Rate-limit by computational cost (credits/tokens per request) not by request count. Pricing and abuse protection align naturally.
If no
Request-count limits are simpler and sufficient when endpoint costs are roughly uniform.
Rate Limiting & Abuse Prevention
Do specific features (uploads, AI generations) have their own cost or quota model?
If yes
Add per-feature limits in addition to global ones. A user at their upload quota should still be able to read the API.
If no
Per-route limits are enough and keep configuration centralized.
Rate Limiting & Abuse Prevention
Is this a public developer API with SDKs / third-party integrations?
If yes
Always return X-RateLimit-Limit, X-RateLimit-Remaining, X-RateLimit-Reset, and Retry-After headers. Well-behaved clients need them to back off correctly.
If no
Minimum viable is Retry-After on 429 responses — detailed headers are nice-to-have for internal APIs.
Rate Limiting & Abuse Prevention
Do you have health checks, metrics endpoints, or internal traffic hitting rate-limited routes?
If yes
Exempt health checks and internal service-to-service calls by IP allowlist or dedicated service tokens. Otherwise monitoring will trip your own limits.
If no
Default behavior — all traffic counts — is simpler and auditable.
Rate Limiting & Abuse Prevention
Do you have authentication endpoints at risk of credential stuffing?
If yes
Rate-limit failed logins separately (per-account + per-IP), with exponential backoff and lockout after N attempts. Combine with CAPTCHA on threshold.
If no
General per-IP limits are insufficient for auth — always treat login and password reset as a separate budget.
Onboarding & Activation
Do you know what the "aha moment" / activation event is for your product?
If yes
Design onboarding backwards from that event. Every step should reduce friction to it.
If no
Fix this before investing in onboarding UI. Instrument product events and find activation empirically.
Onboarding & Activation
Is the first use of your product collaborative (requires inviting a teammate)?
If yes
Surface the invite action prominently in empty states or checklist; single-user usage is often not the activated state.
If no
Optimize for a single-user first success.
Onboarding & Activation
Is your product self-serve, or sales-led / waitlisted?
If yes
Optimize every step for a frictionless signup: single-field email, magic link, and empty-state-driven first action.
If no
Replace signup with a waitlist form + personal outreach; add a wizard (domain verification, SSO) post-sales.
Onboarding & Activation
Is email verification strictly required before first use?
If yes
Send magic link or OTP, but let the user explore read-only state while waiting. Blocking on verification is a major conversion leak.
If no
Skip upfront verification — prompt later when the user takes an action that actually needs a verified email.
Onboarding & Activation
Would a 1-2 question questionnaire meaningfully personalize the first experience?
If yes
Ask role/use-case upfront and route to a tailored template or empty state. Cap at 2 questions — each additional one costs conversion.
If no
Skip the questionnaire; ship the same empty state to everyone and let them self-select via templates.
Onboarding & Activation
Does your product suffer from the blank-page problem (hard to see value empty)?
If yes
Pre-populate a labeled, deletable sample workspace. Essential for analytics, dashboards, and issue trackers.
If no
An empty-state prompt to "Create your first X" is cleaner and avoids clutter.
Onboarding & Activation
Is team invites in the first session a leading indicator of activation?
If yes
Surface the invite step inside the checklist during onboarding — not after. A team workspace that stays single-user usually churns.
If no
Move invites out of onboarding — prompt only when the user takes a collaborative action.
Onboarding & Activation
Does the product only deliver value once external data is connected (integrations, imports)?
If yes
Make the connect-data step the checklist centerpiece. Offer sample data as a fallback so users can explore before committing.
If no
Skip data connection in onboarding — offer it contextually when the user takes an action that needs it.
Onboarding & Activation
Is your product complex enough that new users will miss key capabilities without guidance?
If yes
Add a short guided tour (under 5 steps) with a clear skip control. Never block the UI behind the tour.
If no
Skip the tour — empty-state prompts and in-app help cover it without the friction.
Onboarding & Activation
Does your product surface more features as users mature (advanced settings, integrations)?
If yes
Progressively disclose — hide admin/API/settings until they are needed. Surface them via contextual prompts when the user is ready.
If no
Show the full surface from day one; simpler mental model.
Onboarding & Activation
Do different user roles (admin, member, viewer) need materially different first experiences?
If yes
Branch onboarding on role — admins get setup checklist (billing, SSO, invites); members land directly in the workspace.
If no
One flow for all users is simpler and easier to iterate on.
Onboarding & Activation
Can your empty states double as the onboarding surface?
If yes
Invest in empty-state-driven onboarding first. Every empty screen should show the next primary action, not marketing copy.
If no
Supplement with a checklist — but fix the empty states first; they will carry users further than any tour.
Onboarding & Activation
Have you defined and instrumented a product activation metric (time-to-value)?
If yes
Track it in your analytics and optimize onboarding against it. Every step should either reduce TTV or get cut.
If no
Instrument this before building onboarding UI — without a metric you are guessing.
Onboarding & Activation
Do a meaningful fraction of signups drop off before activation?
If yes
Enable behavior-triggered activation emails. A nudge at day 1 and day 3 recovers 5–15% of dropped signups.
If no
Skip — nudges on already-activated users feel spammy.
Onboarding & Activation
Do you have the analytics maturity and signup volume to A/B test onboarding variants?
If yes
Use an experimentation framework (Statsig, LaunchDarkly, GrowthBook) and test one variable at a time.
If no
Iterate with qualitative feedback first — A/B tests need thousands of signups per week to reach significance.
Onboarding & Activation
Does your product require payment or a card before the user sees value?
If yes
Only if you can justify it (enterprise, physical goods). For SaaS, defer card collection until after the user reaches their aha moment.
If no
Keep payment setup out of onboarding — gate it on usage or trial expiry.
Onboarding & Activation
Do enterprise customers need to complete setup steps (domain verification, SSO, SCIM) before go-live?
If yes
Build a separate admin wizard post-signup for these. Keep end-user onboarding lightweight; admin work should not block the team.
If no
Skip the enterprise wizard entirely until you have paying enterprise customers requesting it.
Preset
Authentication Methods*
Access Control*
Multi-factor Authentication
Tradeoffs
Each provider requires an OAuth app registration and key rotation policy
Requires IdP partnership and XML-based protocol handling; significant integration work
Permission checks must be applied consistently across every data access path
Conversation Types*
Message History*
Rich Content
Tradeoffs
Message routing logic grows significantly; fan-out to members must be handled carefully
Storage costs grow unbounded; requires indexing strategy for search
Requires object storage (S3/R2) and content moderation policy
Server must fetch external URLs on behalf of users; adds latency and SSRF risk
Delivery Method*
User Control
Tradeoffs
Requires persistent connection infrastructure (e.g. Redis pub/sub, WebSocket server)
Higher server request volume; notifications may lag by poll interval
Requires APNs/FCM credentials and certificate management
Significantly more complex preference storage and UI
Search Approach*
Search Scope*
Tradeoffs
Requires FTS index maintenance; adds write-time overhead
Embedding generation adds latency and API cost per indexed document
Results must be unified and ranked across disparate data models
Storage Backend*
File Processing
Tradeoffs
Not horizontally scalable; lost on server replacement without backup
Higher monthly cost; requires cache invalidation strategy
Upload latency increases; requires AV service integration
Authorization Model*
Permission Scope*
Custom Role Management
Tradeoffs
Fast to build but every 'special case' access rule becomes bespoke code that's hard to audit
Requires a policy engine and relationship store kept in sync with primary data
Every list/read query must filter by ACL — expect query-plan work and caching investment
Support load increases substantially — each customer now has a unique permission configuration
Rate Limit Algorithm*
What to Limit By*
Abuse Prevention Layer
Response Behavior*
Tradeoffs
False positives behind corporate NATs; attackers bypass with rotating proxies
Noisy-neighbor protection — one tenant cannot starve others
Allows bursts but requires a per-identity bucket state in Redis — higher memory footprint
Meaningful latency cost at the edge if the WAF is geographically distant from users
Onboarding Format*
Personalization Signals
Activation Support
Tradeoffs
Controls first-experience but introduces sign-up drop-off proportional to wizard length
Requires event tracking + scheduled jobs + segmentation infrastructure
Staffing cost scales with signup volume — not viable for self-serve products below a certain ACV