What Spec Driven Development changes
In traditional delivery, the specification is a step, often rushed and quickly forgotten. In Niji ARC™, the specification is the product. Agents generate the code, the tests and the documentation directly from it. Nothing is produced without it.
This reversal is not just a matter of tooling. It changes the nature of the risk: functional ambiguities are resolved before generation, when fixing them costs a few hours rather than several sprints. The code delivered rests on a proven target, not on a hypothesis.
Niji ARC™ is the AI-driven delivery methodology developed by Niji. It builds on the principles of Spec Driven Development, which we have battle-tested in production and enriched with our proprietary agents: accessibility, eco-design, automated cyber review.
The 3 principles that make the difference
Business and AI iterate together on the UI and features before full generation. Journeys are validated and expectations aligned upfront, when change costs the least. The code is then generated against a proven target, not a hypothesis. This is not decorative mockup work: it is a convergence step that eliminates the debt of misunderstanding.
AI excels at generating; traditional tooling remains the most reliable way to verify. ARC orchestrates both in CI/CD (code quality metrics, code coverage, tests, accessibility, cybersecurity, performance and token consumption) to get the best of each approach at the best cost. AI generates. The pipeline verifies. Together, they guarantee.
Maintainability is a design constraint from the very first specification. ARC does not deliver a brilliant POC that degrades within six months. It delivers products built to last, to be maintained and to keep their quality over time, well beyond the first release.
ARC, step by step
The methodology unfolds in five chained phases, in a continuous flow. A sponsor demo every 72 hours. Nothing goes to production without a measured value threshold.
Business rules are formalized with the sponsor. The spec becomes the delivery contract: exhaustive, verifiable, traceable. Nothing is generated without it.
Business and AI iterate on the UI and features. Journeys are validated, ambiguities resolved. The cost of change is still minimal. This is where it gets absorbed.
SDD agents generate code, tests and documentation from the spec. AI Engineers orchestrate, validate the outputs and manage the quality checkpoints. Generation works against a precise target.
Automated pipeline: code quality metrics, test coverage, CVEs, AI Act compliance, accessibility (RGAA, the French accessibility standard), performance and token consumption. Every gate is blocking. No compromises.
Maintainability is a design constraint, not a step bolted on afterward. Every release builds in long-term quality criteria: scalability, code readability, operating cost.
Why this is not industrialized vibe coding
The most common criticism leveled at agentic delivery: "you are just running an LLM on your specs." ARC answers this criticism structurally.
- Pre-prototyping eliminates functional drift before it costs anything.
- Deterministic CI/CD guarantees that what AI generates is actually compliant, not just syntactically valid.
- Niji's proprietary agents (accessibility, eco-design, cyber) add layers of verification that generic tools do not cover.
- BUILD for RUN builds operational constraints in from the design stage, rather than catching up after delivery.
The result: time-to-market divided by 5, with measurable quality that exceeds the standards of traditional delivery.
Implementation in your organization
ARC is activated as part of Niji's AI Factory offer. The AI-native squad (AI Product Builder, AI Architect, AI Engineers) deploys the methodology in context, adapted to your stack and your regulatory constraints.
First sprint: framing on the morning of day 1, pre-prototyping that afternoon, agentic build on day 2, sponsor demo on day 3. Production release if the gates pass. The next cycle starts immediately.
Framing with no strings attached. Every Niji AI-DRIVEN engagement starts with a 2 to 6 week AI Strategy & Change phase, with an ROI quantified in euros per year before any delivery commitment. No ARC sprint without a validated business case.