Meet the Author

Background

Daniel spent the first seven years of his career as a backend engineer at B2B SaaS companies, building the kind of systems where a missing field in a spec could mean an overcharged customer, a failed payment retry, or a deployment that could not be safely rolled back.

In 2019 he moved into a tech lead role, responsible for engineering handoffs, spec review gates, and QA alignment across teams of 8–15 engineers. That experience — watching well-intentioned teams ship rework because the requirement document left too much to interpretation — is the direct origin of everything published on this site.

Daniel started Spec Coding in November 2025 to give teams a practical reference that covers the full delivery lifecycle: from writing the first draft of a spec, to defining acceptance criteria that QA can actually execute, to designing the rollback plan before code is merged. Employer names are intentionally omitted here; the site does not claim endorsement from any past client, employer, or platform.

Identity and Verification

This page is the canonical author profile used by Spec Coding. Public links are listed in one place so readers can distinguish the editor profile from unrelated accounts with similar names.

• Public profiles: GitHub and X / Twitter.
• Editorial contact: corrections and source questions go to [email protected].
• Scope of claims: career examples are anonymized engineering scenarios, not claims of endorsement by named employers or customers.
• Updates: material author-page changes are reflected in the last-updated date and, when relevant, the site changelog or Editorial Policy.

Experience Timeline

What Daniel Writes About

Every article on Spec Coding is drawn from a real delivery scenario Daniel has encountered or has been consulted on. Topics include:

• Spec-first adoption — how to introduce specification discipline to a team already mid-sprint, without disrupting velocity.
• API contracts — versioning strategies, contract testing pipelines, error taxonomy, and backward compatibility review.
• Acceptance criteria — writing Given/When/Then scenarios that QA can execute without interviewing the author.
• Risk-heavy patterns — idempotency, concurrency, rollout/rollback design, and the postmortem behind common billing incidents.
• Reusable templates — downloadable spec documents, PRD-to-spec conversion guides, and review scorecard tools.

Editorial Accountability

Spec Coding articles are reviewed before publication and updated when readers report outdated examples, unclear guidance, or factual issues. The full publishing and correction process is documented in the Editorial Policy.

For factual corrections, feedback, or collaboration inquiries, use the contact page or email [email protected]. Editorial messages are reviewed within three business days.

How Recommendations Are Formed

Recommendations on Spec Coding start from repeated delivery failures: unclear scope, untestable acceptance criteria, unsafe API changes, database migrations without rollback paths, or AI-generated code that drifted beyond the agreed spec. Daniel turns those failure modes into checklists, templates, and examples that teams can apply before implementation begins.

The site intentionally favors practical constraints over broad methodology claims. If a guide recommends a pattern, it should explain what risk the pattern controls, what evidence reviewers should look for, and when the pattern may be too heavy for a small change.

When reader feedback shows that an example is too generic, Daniel usually adds a decision rule, failure path, or review question rather than simply lengthening the article. The editorial goal is practical judgment, not volume.

Source-to-Article Trail

Spec Coding does not publish client names or private incident details. Instead, Daniel keeps the operational pattern and removes identifying context. The published version should still preserve the decision pressure that made the scenario useful.

Private source pattern:
- billing refund retried after provider timeout
- support team could create a second refund while first was pending
- rollback depended on payment provider confirmation

Published teaching pattern:
- idempotency key must define replay behavior
- support UI must respect pending provider state
- rollback note must name the point where reversal stops being safe

This is the main editorial test: remove private facts, keep the decision that would help another team avoid the same failure.

Evidence Rules for Examples

Examples are revised when they cannot answer three reviewer questions: what changed, who owns the decision, and what evidence would prove the behavior before release. That is why recent updates add copy-ready review blocks, field notes, and concrete stop conditions rather than more abstract explanation.

• For API examples: name the consumer, compatibility class, and contract evidence.
• For AI coding examples: name the allowed scope, generated-risk class, and human sign-off point.
• For migration examples: name table size, backfill phase, rollback limit, and rehearsal evidence.
• For acceptance criteria: name actor, trigger, observable result, and at least one negative path.

How Field Experience Shapes the Examples

Daniel treats examples as small simulations of real delivery work. A useful example should name the actor, the system boundary, the state change, the failure path, and the evidence a reviewer would inspect before release. That is why many Spec Coding examples mention idempotency keys, rollback triggers, permission checks, migration risk, and observable production signals instead of staying at the level of generic best practice.

When an article is updated, the first pass is not "can this be longer?" but "can a reader use this to prevent a specific mistake this week?" If the answer is unclear, the section is rewritten around a concrete decision point, a review question, or a before/after comparison.

Public Project Signals

Spec Coding keeps public reference points separate from private client history. Readers can verify the maintainer profile through the listed GitHub and X accounts, then inspect site-level policy and content changes through the public changelog.

• Repository signal: public template work is linked through spec-templates.
• Editorial signal: material changes to policy, naming, curation, and topic hubs are logged on the changelog page.
• Correction signal: reader corrections route through contact and are handled under the Editorial Policy.

Selected Articles by Daniel Marsh

• What Is Spec-First Development? (Complete Guide)
• PRD vs Technical Spec: What's the Difference?
• How to Write Testable Software Specifications
• Spec-First vs Agile: Conflict or Complement?
• 10 Common Mistakes in Software Specifications
• Postmortem: Preventing a Billing Incident with Spec-First
• Versioning Strategies for API Contracts
• Contract Testing Plan: From OpenAPI to CI
• View all articles →

Open source projects

• spec-kit — Markdown specification templates for spec-first software development. Includes feature specs, API contracts, database migration specs, incident postmortems, and review checklists.
• openapi-spec-starter — OpenAPI starter kit with CI-integrated contract testing. Includes Spectral linting, Prism mock validation, Schemathesis fuzz testing, and a GitHub Actions workflow.

Current Editorial Priorities

Daniel is currently focused on making every core page useful without extra context: stronger examples for templates, clearer review gates for tools, better Chinese-language parity, and more explicit maintenance notes for resources and policy pages. The goal is for a reader to leave each page with a concrete next action, not just a definition.

Find Daniel Online

• GitHub: GitHub — spec-first development resources
• Email: [email protected]
• Site: spec-coding.dev