What SPDD is
Structured Prompt Driven Development (SPDD) is a specific, opinionated way of doing spec-driven development. Where the broad category leaves the shape of the spec and the placement of review up to you, SPDD commits to answers: a fixed set of structured artifacts, a fixed set of human gates, and standards that are applied automatically rather than remembered.
The name is literal. Instead of prompting an AI tool once and hoping, you move an idea through structured stages, each one drafted by AI and reviewed by a human before it advances. A misunderstanding costs less the earlier you catch it, so SPDD front-loads that catching into small, focused reviews rather than one overwhelming one at the end.
SPDD is published openly as openspdd, the open specification of the methodology. You can run SPDD with any stack, any AI provider, and any editor. REEZN is a platform built specifically to run it as a team, but the methodology does not belong to any one tool.
Principles
The stages
SPDD runs an idea through the following stages. REEZN’s pipeline embodies them directly, and they are the concrete worked example of the general specify-review- implement-verify loop:
The implementation, verification, and sign-off tail is where SPDD closes the loop from an approved spec all the way to a reviewed pull request. In REEZN it is a premium capability; the specify-and-review core runs on any plan.
The REASONS canvas
The blueprint stage uses a structured canvas whose sections spell the acronym REASONS. Each section answers a specific question, grounded in the approved analysis, so no two blueprints skip the same thing:
A separate REASONS canvas is generated for every service a feature touches, so each plan speaks in terms of that service’s real stack and the right reviewer signs off on the part they own.
Norms, safeguards, and organizational memory
What makes SPDD governed rather than merely structured is that your standards are first-class objects, not reminders. Norms are the conventions and proven patterns your team follows; they guide. Safeguards are the hard limits that must never be crossed (privacy boundaries, usage caps, compliance rules); they constrain. Both are injected into every AI generation, scoped org-wide or per project, so each analysis and blueprint is built to your real rules rather than generic best practice. A safeguard violation caught at verification blocks delivery outright unless a human explicitly overrides it, on the record.
Alongside them, every approved plan, norm, and document teaches an organizational knowledge base that the AI consults while drafting. Context compounds instead of being re-explained: the fiftieth plan is written knowing what the first forty-nine established. Standards that once required slack headcount to maintain, written conventions, structured review, decision records, become nearly free when AI drafts and a human approves.
Why the gates go where they do
SPDD places its two core review gates deliberately, at the two cheapest points to change direction. The first gate, on the analysis, catches a misunderstood requirement while it is still a comment on a document. The second, on the blueprint, catches a wrong design before any code exists. Both sit before implementation, because a mistake caught on the page costs a sentence to fix and the same mistake caught in a shipped feature costs an incident.
Splitting "did we understand it?" from "how should we build it?" into two small reviews, rather than one large one, is what keeps each gate focused enough that reviewers actually do it. The verification sign-off then closes the loop at the far end: the spec that opened the work is the yardstick the finished work is checked against.
The methodology is open and tool-agnostic: run SPDD with any stack, any provider, any editor. REEZN is the platform built to run it as a team, with the roles, gates, safeguards, and memory enforced by the server rather than by discipline.