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PRJ-04 · Internal API Platform

Luce Backend Internal Apps

Rails and GraphQL backend behind Luce's internal apps, client websites, and mobile apps.

2025 — 2026 · 12 months
production Sentry errors
−73%
high-severity security issues
0
fast API call performance
+32%

02 / Decisions

  1. DEC-01 Tests first, upgrade second

    The Rails monolith had 26% test coverage, and its GraphQL API served internal admin apps, client websites, and mobile apps. An upgrade could break any of them without a single test failing.

    Turned down

    Upgrade first, then fix what breaks in production

    Chose

    Grew an RSpec and VCR safety net from 26% to 77% coverage over six months, then upgraded Rails 7.0 → 7.2 and fixed the transaction rollback, encryption, and dependency issues the tests caught.

    Cost
    A slower start. Months of test work came before the upgrade itself.
    Proof
    Rails 7.0 → 7.2 shipped, up-to-date backend dependencies went from 26% to 83%, and production Sentry errors fell by 73%.

03 / What I did

  1. Led backend scalability, security, and refactoring work on Luce's Ruby on Rails monolith, whose GraphQL API serves internal admin apps, client websites, and mobile apps.

  2. Cut production Sentry errors by 73%, removed all high-severity security issues, and improved fast API calls by 32% (p95 <500ms).

04 / Stack