QA & Testing

A fintech app had zero automated tests after three years of shipping, and every release felt like a coin flip. We built a Playwright suite covering 120 critical user flows, a Vitest unit suite reaching 70 percent coverage on business logic, and Pact contract tests between their API and mobile client, catching 47 regressions in the first release and cutting QA cycle time from 4 days to 8 hours.

A B2B SaaS platform was hitting P99 latency spikes under concurrent load that did not show up in normal testing. We built a k6 load test suite modeling realistic peak traffic, identified a single Postgres query with a missing composite index that was 120 times slower under load, and fixed it along with four other query-level bottlenecks, cutting P99 latency at peak from 8.2 seconds to under 600ms.

A healthcare app needed WCAG 2.2 AA compliance before a launch with a state contract. We ran an axe-core automated audit identifying 380 issues, prioritized by severity, fixed the top 140 blocking issues over four weeks, and ran a final manual audit with a screen reader user before launch, passing the state accessibility review on the first submission.

An e-commerce platform lost three weekend hours of sales to a checkout regression that their existing tests did not catch. We rebuilt their E2E suite in Playwright with real payment method testing against Stripe test mode, added visual regression testing with Percy on the checkout flow, and integrated tests into their deploy pipeline, catching two similar regressions in the next two months before they reached production.

A healthtech startup preparing for SOC 2 Type II needed automated access control tests, encryption validation, and audit log verification. We built a compliance-focused test suite with test evidence automatically uploaded to Vanta, covering every Type II common criteria control, and they passed their audit with zero findings on first attempt.

A SaaS company had a Cypress test suite with a 40 percent flake rate that the team had stopped trusting. We migrated to Playwright over six weeks, refactored the page object model, identified and fixed seven race conditions that Cypress was hiding, and brought the flake rate down to under 2 percent, restoring the team's trust in the suite.

A mobile gaming company needed performance testing for a new social feature that would fan out to all a player's friends. We built a k6 load test modeling the viral-fan-out pattern, identified a Redis pub/sub hotspot that would have melted at 50k concurrent users, and redesigned the data path to Kafka with consumer groups before launch.

A multinational retailer needed a penetration test on their new customer portal before launch. We ran a two-week structured pen test with a three-engineer team, identified 14 findings including one critical CSRF vulnerability and one high-severity authorization flaw, worked with their team on remediation, and re-tested to verify fixes before the portal went live.

A regulated financial platform was shipping data-layer changes that occasionally broke downstream analytics. We built a contract testing layer with Pact between their data producers and consumers, with PR-level enforcement, eliminating the class of breakages entirely over six months and cutting their incident rate on data issues by 85 percent.

A B2B SaaS had a test suite that took 52 minutes to run, which meant the team was merging without running it. We ran a test optimization sprint, sharded the suite across 16 parallel runners, switched expensive setup to shared fixtures, and identified 80 redundant tests to delete, cutting runtime to 6 minutes and restoring the team's ability to run the full suite on every PR.

A marketplace platform had a security disclosure for an authorization bug that they wanted to prevent from recurring. We added authorization test fixtures covering every role and resource combination, integrated Semgrep with custom rules matching their authorization pattern, and built a regression test on the specific bug, closing the class of vulnerability.

A design tool startup was shipping a real-time collaborative editor and needed to validate that CRDT conflict resolution worked under adversarial network conditions. We built a Playwright-based test harness simulating two clients with network partitions, latency, and message reordering, caught three bugs in their merge logic before launch, and converted the harness into an ongoing regression suite.