01 · Home
A daily read, not a feed.
The home screen turns sleep and recovery data from the user's wearable into one score and four plain-language readings. No likes, no followers, nothing to scroll. Oslyn is one tap away.
A private growth app, built and run end to end.
A private growth platform for men that combines journaling, an AI coach and recovery sessions in one app. There are no public feeds, and privacy is on by default.
- Client
- Brologue
- Engagement
- Product team since Nov 2025
- Platforms
- iOS · Android · Web
- Status
- Live
01 / The brief
Brologue doesn't have an in-house engineering team. We are it: the app, the AI, the servers and the growth tools, from first commit to every store release.
The product is built for men who want to get their life in order without performing it for an audience. That set two constraints from day one: there are no public feeds, and privacy is the default, not a setting.
So the engineering work is as much about restraint as features: an AI coach that asks before it acts on anyone's behalf, personal details scrubbed from the background AI jobs, and every feature instrumented so decisions come from how people actually use it.
- Product engineering
- AI & voice
- Integrations
- DevOps
- Growth tooling
The product, screen by screen
02 / The product02 · AI coach
Oslyn remembers, and asks before it acts.
Oslyn is an agent with long-term memory, retrieval over the user's journal and tools across the app: sleep, tasks, calendar, and connected accounts like Gmail, Notion and Strava. Users can type, send a photo or talk out loud. Anything that acts outside the app waits for their approval.
03 · Programme
Twelve weeks, one standard at a time.
A structured 12-week challenge across the six pillars, with weekly themes, daily focus prompts and a streak to keep. Weekly command briefs summarise what changed and what to pull on next.
04 · Recovery & body
Sleep, breath and training in the same place.
Sleep tracking from Oura and Ultrahuman, a library of sleep sounds and guided breathing, and a levelled workout plan. Meditation audio is generated by background workers on Kokoro TTS deployments we run ourselves.
How it's put together
03 / Architecture
Boring where it can be, careful where it matters. One API, one database, queues for anything slow.
Clients
01 · What people touch
iOS & Android app
Expo · React Native · widget
brologue.com
Next.js · blog & guides
Support admin
React · support & analytics
Edge
02 · Identity, API and real-time
Clerk
Auth · user webhooks
API
Express · Bun · systemd
LiveKit
Real-time voice
Core
03 · Where the product lives
Oslyn
Agent · memory · approvals
PostgreSQL
Drizzle · pgvector
Redis · BullMQ
Workers · cron · wearable sync
Providers
04 · Rented, swappable
Groq · OpenRouter
LLMs · Whisper
ElevenLabs
Live speech · Orpheus fallback
Kokoro TTS
Meditation audio · self-run
Composio
Gmail · Notion · Strava
Oura · Ultrahuman
Sleep & recovery data
Stripe
Subscriptions & credits
Resend · Expo push
Email & notifications
PostHog
Product analytics
Detail · One Oslyn turn
Nothing leaves the app without a yes.
Each turn, a fast model classifies the message, which decides the tools and memory Oslyn gets. Reading is free; anything that acts for the user outside the app waits for their approval, and that answer is stored on the thread as the audit trail.
- 01
Message
Text, a photo, or speech transcribed by Whisper
- 02
Classify
A fast model reads the intent and picks the tools and memory
- 03
Context
Profile, long-term memory and journal retrieval via pgvector
- 04
Act
Tools read sleep, tasks and calendar, and connected apps
- 05
Approve
Emails, calendar events and task changes wait for a yes
- 06
Stream
Tokens to the app, or on to ElevenLabs as speech
What we build and run
04 / Scope- 01
Mobile app
An Expo / React Native app for iOS and Android that covers journaling, recovery audio, tracking across the six pillars, and an Android home-screen widget.
- Expo
- React Native
- Skia
- TanStack Query
- 02
Oslyn, the AI coach
An agent with memory, retrieval over the user's journal, photos, and tools across the app and connected accounts. Anything that acts outside the app, like sending an email, waits for the user's approval.
- AI SDK
- Groq
- OpenRouter
- pgvector
- Composio
- 03
Voice
Talk to Oslyn out loud: Whisper transcribes, ElevenLabs Flash speaks, and Groq's Orpheus takes over if ElevenLabs is unavailable. Meditation audio comes from Kokoro TTS deployments we run ourselves.
- LiveKit
- Whisper
- ElevenLabs
- Orpheus
- Kokoro TTS
- 04
Backend & data
The API, database, background workers and scheduled jobs behind every feature, plus auth, credits and push notifications.
- Express
- Bun
- PostgreSQL
- Drizzle
- Redis / BullMQ
- Clerk
- 05
Integrations & billing
Sleep and recovery data from Oura and Ultrahuman, Google Calendar, Gmail, Notion and Strava for Oslyn, Stripe subscriptions and credits, and transactional email.
- Oura
- Ultrahuman
- Composio
- Google Calendar
- Stripe
- Resend
- 06
Web, ops & growth
The content site with its blog, answers and comparison pages, an internal support and analytics dashboard, production servers, store releases, and an AI pipeline that turns a brief into vertical video ads.
- Next.js
- PostHog
- EAS
- Linux / systemd
- fal.ai
- ffmpeg
- Engagement started
- Nov 2025
- Platforms shipped
- 3
- Codebases we run
- 6
- Commits shipped
- 840+
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