Making large-scale automation safe.
Case studies, essays, and working systems from safety-critical platform work.
Explore the workPlatform ownership, safety checks, and regional isolation for critical operations.
A retrieval system with refusal guardrails and evaluation checks in public source.
Inspect a training recommendation for a sample athlete, with no login required.
What this site is
Caskey Engineering is the working notebook of Eric Caskey, a Senior Software Engineer at Amazon. He owns a multi-region workflow orchestration control plane and an infrastructure monitoring platform. The rule behind both, and behind everything published here, is that automation at scale is only as safe as the checks that run before it acts. Every workflow on that control plane passes mandatory safety checks before an automated operation begins, and nobody can opt out of the environment isolation guardrail.
The site has three parts. Case studies document the systems: standardized monitoring across a fleet of service teams at Amazon, the orchestration platform and its guardrails, and earlier work at Prudential Financial from 2013 to 2021 covering enterprise monitoring, crisis-era reporting, and an MFA self-service platform. The blog records how the work gets done, with essays on spec-driven development, backtesting without fooling yourself, and running an AI-assisted engineering team of one. The lab holds working software you can use without an account: a factor-scored public stock board, a set of 3D market visualizations, a marathon coach demo, and a grader for a sample portfolio.
How the work gets done
Every feature starts as a written spec in a versioned repository. AI coding agents implement against the spec, and a local-first CI gate runs the tests, the disclosure scan, and the voice check before a push is allowed. The method is documented in the lesson series and in the essays on institutional memory and model routing, and it is the same method used to build this site.
The finance material follows one more rule. The engine grades companies on quality, valuation, momentum, and health from public data, publishes its methodology, and keeps a pre-registered record of its forecasts so they can be scored later. It is an engineering exercise in measuring your own edge honestly. Nothing here is investment advice.
Where to start
Read the workflow orchestration case study for the safety-check design. Read The Pipeline That Ate Itself for what happens when a pipeline reports success while feeding on its own output. Open the public board to see the engine grade a live universe of names. Then browse everything by system, method, or timeline.
Common questions
- Who is Eric Caskey?
- Eric Caskey is a Senior Software Engineer at Amazon. He owns a multi-region workflow orchestration platform and an infrastructure monitoring platform. He worked at Prudential Financial from 2013 to 2021 on enterprise monitoring, reporting, and an MFA self-service platform. He writes at caskeycoding.com and ericcaskey.com.
- What is Caskey Engineering?
- Caskey Engineering is the engineering brand and publishing home of Eric Caskey: case studies, a technical blog, and an interactive lab, built with spec-driven development and safety-first infrastructure engineering.
- What is spec-driven development?
- Spec-driven development means every feature begins as a written specification in a versioned repository, and code, tests, and AI agents implement against that spec. On this site the specs live in a separate repository and a local CI gate checks every change against them before it can be pushed.
- Is the finance content investment advice?
- No. The finance tools and essays are educational engineering: a public factor engine, its published methodology, and pre-registered forecasts scored against a benchmark. Nothing on the site is a recommendation to buy or sell anything.