BMAD vs. Spek Kit vs. Open Spec: Which AI Coding Framework Reigns Supreme?

You probably use an AI to help you code. But what if I told you that just typing vague, unspecific prompts into a chat window—what some people call “vibe-coding”—is a dead end for any serious project? It leads to poor output, lost context, and code that’s impossible to maintain.

The industry knows this. A new wave of structured AI development methodologies is here to fix it. But are they any good? I decided to find out.

I took one project—building a landing page—and built it three separate times. I used three different AI frameworks: the heavyweight BMAD method, GitHub’s Spek Kit, and the fast-moving Open Spec. One of these took eight hours to build a single page. Another took just under two.

In this article, I’m going to show you everything: the setup, the slow parts, the fast parts, and the final results. I’ll break down how they stack up against each other. By the end, you’ll know exactly which framework is right for you and which one might just be a colossal waste of time.

The Project: A Real-World Test

Building a simple landing page isn’t enough for a true test. So, I added a few challenges.

Tech Stack:

• Next.js
• Tailwind CSS
• Shad CN UI

Core Requirements: The page needed three live API integrations to be considered a success:

1. YouTube Data API: To fetch and display a real-time subscriber count.
2. MailChimp API: For a fully functional email sign-up form.
3. Embedded YouTube Players: To showcase a selection of top-performing videos.

To ensure a fair comparison, I prepared a detailed input.md file describing every section and used the exact same file and AI model for all three attempts.

Now let’s see how they did.

The Beast: BMAD

First up is BMAD, a framework that simulates an entire agile software team using different AI agents.

Setup: Installation is a single command. The initial phase was all about documentation. I orchestrated the different AI personas—the project manager, the UX expert, and the architect—to produce massive specification documents.

The Process: The real work, and the real time sink, came after the initial setup. The project was broken down into four epics, each containing three to five user stories. For every single story, I had to manually run a loop:

1. Call the Scrum Master agent to draft the story.
2. Hand it to the Developer agent to write the code.
3. Pass the finished code to the QA agent for review.

This entire process for one landing page took eight hours.

Why so long? Because I was chained to the computer, manually orchestrating every single step. Each agent would work for several minutes, but I couldn’t just walk away. I had to be there to trigger the next agent in the sequence. The process went a little faster when I opened three separate terminals—one for the Scrum Master, one for the developer, and one for QA. But every time I switched agents, I had to clear the context to keep them focused. It took up to a minute for each new persona to initialize and get up to speed. It was incredibly tiresome.

By the end, I was completely drained and genuinely felt, “I could have done this faster myself.”

The Result: Was the result worth it? Honestly, the result was impressive. Thanks to the dedicated UX Expert agent, the design system it created was more advanced than the others. And crucially, all the integrations worked on the first try. The final website looked and felt incredibly solid. But eight hours is a tough price to pay.

The Developer’s Toolkit: GitHub’s Spek Kit

Next up was GitHub’s Spek Kit. Unlike BMAD’s team of agents, Spek Kit is a lightweight toolkit designed to help a developer work better with a single AI assistant.

Setup: Installation involves using uv, a Python package installer from Astral.

# Example installation command
uv pip install spek-kit

The Process: The process is built around four simple slash commands in your AI chat:

• /specify: Takes the input.md and generates a formal spec.md file.
• /plan: Reads the spec and creates a technical plan.md file.
• /tasks: Breaks the plan into a checklist of small, manageable tasks.
• /implement: Executes the checklist and generates the code.

A standout feature of Spek Kit is the constitution.md file. Here, you can define high-level project rules, like “Always use Test-Driven Development” or specific design principles. The AI must follow this constitution at all times.

The difference was night and day. The entire process took just under two hours.

The Result: When I came back later to add the YouTube players as a new feature, the whole specify-plan-tasks-implement cycle was incredibly fast. The implementation was brilliant. Instead of loading the heavy YouTube players immediately, it first fetched static cover images from YouTube’s CDN. The page loaded with just these lightweight images and a play button. Only when you hit play did it load the actual YouTube player JavaScript. This gave the page a huge performance boost.

The integrations worked perfectly. The AI even hit its context window limit once, but it paused, summarized its progress, and let me continue right where it left off. This felt like a tool made for developers.

The Need for Speed: Open Spec

Last up was Open Spec. This one feels very similar to Spek Kit. It’s fast, developer-focused, and aims to make the specification the single source of truth.

Setup: The installation instructions are simple. You first install the CLI tool globally with npm.

npm install -g openspec

Then, you navigate to your project and run openspec init. This sets up the project and configures your AI assistant with the right instructions.

The Process: The workflow is even simpler than Spek Kit’s. It’s built around a proposal system. For any new work, you ask your AI to create a change proposal. The AI creates a new folder for this change. Inside, it generates a proposal.md, a tasks.md, and “spec deltas”—small files showing only the proposed changes.

Once you approve, you tell the AI to implement the change. When it’s done, you tell the AI to archive the change, which merges the “spec deltas” into the main project specs.

The Result: This was by far the fastest experience. After a few hiccups at the start (because I forgot to add my design colors and had to restart), the first implementation was stunningly fast. It took just seven minutes for the AI to generate a fully functional website with all three integrations working perfectly.

Because it was so fast, I had time for a second iteration. I described the first version back to the AI and asked it to modernize the design. A few minutes later, I had animated logos and smooth scroll-reveal effects.

Head-to-Head: A Philosophical Divide

So, we have three functional websites, but the processes to get there were radically different. Let’s break down the core philosophies.

BMAD:

• Approach: Top-down, process-driven.
• Philosophy: A highly structured process simulating a specialized team will produce the most consistent results. The process is the star of the show.
• Human Role: High-level orchestrator or manager. It’s human-to-AI delegation.
• Scope: Macro-level. It manages the entire project lifecycle and has a high adoption overhead.

Spek Kit & Open Spec:

• Approach: Bottom-up, developer-centric.
• Philosophy: Empower the individual developer, using the AI as a powerful assistant to execute a clear plan. The developer is the star.
• Human Role: Implementer, actively steering a single AI co-pilot. It’s human-AI collaboration.
• Scope: Micro-level. Focused on a single feature or task with low adoption overhead.

This explains everything. BMAD took eight hours because it was building an entire governance structure. Spek Kit and Open Spec took under two hours because they were laser-focused on implementing a feature.

The Verdict: Which One Should You Use?

So, which one is right for you?

Choose BMAD if… You’re in a large-scale enterprise environment. The deep documentation and process control of BMAD make it a powerful choice for industries like finance and healthcare that are hesitant to adopt AI due to perceived risks. BMAD’s rigorous, auditable process directly addresses these fears. Its end-to-end versioning in git creates an “audit defense blueprint” where every decision is traceable. For a solo developer, the current version is overkill, but for a large corporation needing that level of control, BMAD is a critical tool.

Note: BMAD has a groundbreaking V6 version in the works, but it’s currently in alpha for early adopters only. This test was conducted with the stable version.

Choose Spek Kit or Open Spec if… You’re a solo developer or part of a smaller, agile team. For the rest of us, the choice is between Spek Kit and Open Spec. They felt very similar in practice. Both are fast, effective, and produce high-quality results. As a developer, I was able to quickly find and fix any issues that came up.

If I had to pick one for my daily workflow, my personal recommendation would be Spek Kit. It is maintained by a large company, GitHub, and has a very large community with over 35,000 stars. It’s being actively developed and feels like it has a stable, long-term future. Open Spec is also developing quickly, but the corporate backing and huge community of Spek Kit give it the edge for me right now.

The most important takeaway is this: structured AI development is here, and it’s a huge improvement over “vibe-coding.” Whether you need the control of BMAD or the speed of Spek Kit, using a methodology will make your AI-assisted work more predictable, scalable, and professional.