Jose Mucientes

At Spotify, artist relations teams manually scheduled email campaigns to promote artist merchandise via an internal messaging system. This process required significant manual effort and didn't scale as the number of artists grew.

I was tasked with designing and delivering a self-serve back-end service from scratch that would allow campaigns to be created and scheduled programmatically via Spotify for artists' tools. The system needed to be scalable, reliable, and flexible enough to support future campaign types.

ACTION
I gathered requirements from stakeholders, designed the system end-to-end, and wrote multiple RFCs: one covering the overall microservice architecture and API design, and another focused on selecting the appropriate storage solution. I also implemented the service as a standalone Java microservice with a clear domain model around campaigns, schedules, and targeting rules.

It exposed REST APIs and a gRPC endpoint, enabling artist teams to configure and schedule merch campaigns and Live Artist Room campaigns themselves.

The service shipped successfully, eliminating the need for artist relations to schedule campaigns manually and significantly improving scalability and operational efficiency.

Our team led a project from scratch to create a digital revenue source for artists beyond music streaming royalties.

After multiple MVPs and user research, Live Artist Rooms was successfully launched in September 2023, generating an average of $2,000 per room for the artist, including premium-tier ticketed access to the room and merchandise sales.

As a key contributor to the project, my most notable contributions include:

• Setting up a Cloud SQL Database for the Live Rooms system.
• Implementing multiple features in the back end, including banning users, moderators, etc.
• Setting up a development environment and running multiple test sessions.
• Extending the Fan Commerce Campaigns service to support sending email invites to the Live Artist Room to the artists' top fans.
• Working 24/7 on-call rotation, actively contributing to our runbooks and monitoring systems.

When I joined Spotify's artists' mobile team, we owned the Artist Profile experience—profile photo, bio, playlists, background image. The app only used HTTP caching. It failed due to weak connectivity in subways, tour venues, and music festivals. Additionally, edits often failed silently, and creators lost trust in the tool.

I set off to make Artist Profile offline-first so creators could reliably view and edit profiles anywhere, with instant loads, pending edits, and conflict-safe sync.

ACTIONS
• Implementing telemetry enhancements to tag network-quality tiers, i.e., strong, weak, and offline, to quantify improvement.
• Redesigning the data layer using Room and SQLite.
• Adding tables for artists, releases, playlists, and artist pics.
• Implementing DB-first UI load (<200ms) with background refresh.
• Utilizing WorkManager and RxJava for retrying updates with exponential backoff.
• Handling explicit conflict resolution UX for high-stakes edits.

IMPACT
As a result, P90 load time went from around 1.4s to under 200ms. The feature became an internal reliability benchmark and was reused by other teams to justify moving to an offline-first approach. Artists could edit profiles confidently anywhere, boosting trust and usage.

Pocket Chef is an offline-first Android application that helps users discover, save, and manage recipes with a focus on real-world reliability and scalability.

It is built entirely in Kotlin, Pocket Chef uses Jetpack Compose, Hilt, Coroutines, and Room on the client side, and paired with a Ktor and PostgreSQL back end. The app is designed around an anonymous-first model: users can start cooking immediately without signing up, then later create an account and seamlessly sync their data across devices.

A key architectural challenge tackled in Pocket Chef is offline-first data synchronization. The app handles local persistence, conflict resolution, and server-authoritative timestamps, ensuring a smooth experience even with intermittent connectivity. Authentication, session management, and sync are implemented with production constraints in mind rather than demo shortcuts.

The project emphasizes clean architecture, testability, and realistic scale, including end-to-end UI tests, dependency-injected fakes, and a data model capable of supporting hundreds of recipes, ingredients, tags, and relationships.

Pocket Chef is in active development, with the first MVP launch targeted for February 2026.