Miguel Almeida
← Selected work

Reliability case study

Ghostwriter

Treat authentication success as a database contract, not a UI event

Registration appeared complete before the expected database state existed, exposing migration drift and an incomplete success boundary.

Focused reliability case study based on the registration incident and the controls added afterward.

Read case studyPrivate repositoryNo public demo
Ghostwriter editorial interface with an author selector, mood control, and an illustrated writer at a typewriter.
Current product surface · reliability story follows below
RoleFrontend · application reliability
ContextIndependent product
StackNext.js · React · TypeScript · Supabase · CSP · automated tests

Ownership

What I built and why it mattered

Traced the outage through registration and database state, repaired the success boundary, and added migration drift checks, session-family handling, idle timeout, CSP, consistency checks, and automated regression coverage.

Migration drift guard · session-family behavior · database consistency checks

Reliability sequence

A client transition was not a successful registration.

Incomplete success boundary

The interface moved before the database was ready.

Registration looked complete while the required database state was absent after migration drift.

  1. 01Submit request
  2. 02Client transition
  3. 03Missing database state
  4. 04Later failure

System flow

The working sequence

  1. 01Registration
  2. 02Session creation and renewal
  3. 03Idle timeout
  4. 04Rewrite workspace

Technical judgment

Decisions that define the architecture

01

Move the success boundary behind verified database consistency.

02

Add a migration drift guard instead of relying on local schema assumptions.

03

Model sessions as a family and test expiry and idle behavior.

04

Harden CSP while preserving required application connections.

Evidence ledger

Claims with their boundaries attached

Verified

Registration success boundary

Registration success now depends on the required database state rather than the client transition alone.

Ghostwriter reliability notes
Verified

Migration drift guard

Automated checks detect schema drift before the registration path is treated as healthy.

Ghostwriter reliability notes

Current limits

What this work does not establish

  • This case study covers reliability controls, not model quality.
  • No production user or adoption metrics are claimed.

Need a shorter path?

Ask MiguelLLM for the engineering version.