Recommended Trending OpenSpec Mastery: Production Spec-Driven Workflows for AI Coding Agents
Operationalize SDD with OpenSpec — the open-source spec framework that treats specs the way Git treats code. Master /opsx:propose, /opsx:apply, and /opsx:archive on a real brownfield codebase. CI gates, multi-engineer collaboration, retrofitting legacy specs, and the workflow rituals that make it stick.
Oleksii Anzhiiak
Software Architect, Senior .NET Engineer & Co-Founder
By the end you'll be able to
- Ship OpenSpec on a real brownfield codebase from npm install to spec-gated CI
- Master the /opsx:propose, /opsx:apply, /opsx:archive workflow end-to-end
- Wire openspec validate as a blocking CI step and review spec deltas instead of code diffs
- Retrofit specs onto legacy code using the two-pass descriptive→prescriptive workflow
- Build the team rituals that make spec-driven engineering stick past week three
Is this course for you?
This is right for you if you…
- You finished #28 (SDD Foundations) or #26 (Claude Code Mastery) and want the production tool that operationalises both
- You're a Senior+ engineer ready to commit your team to one SDD framework — and want the senior-architect take on which one
- You're maintaining a brownfield codebase and need a path to spec discipline that doesn't require rewriting everything
Don't take this course if you…
- You haven't internalised SDD yet — take #28 first; OpenSpec without the methodology is just slash commands
- Your team isn't using an agentic coding tool yet — take #26 first to get the daily loop down
- You don't have a real codebase to apply this to — OpenSpec is a production tool, not a sandbox exercise
Who teaches this
Oleksii Anzhiiak
Software Architect, Senior .NET Engineer & Co-Founder
Oleksii Anzhiiak is a Software Architect, Senior .NET Engineer, and Co-Founder of ToyCRM.com and ProfectusLab. With over 15 years of experience, he specializes in distributed systems, cloud infrastructure, high-load backend development, and identity platforms. Oleksii designs complex architectures, builds secure authentication systems, and develops modern engineering education programs that help students achieve real career results.
Currently leads architecture for ToyCRM.com — a multi-tenant CRM platform built on .NET by our team. The same patterns and design decisions used there appear directly in the courses: identity & auth, distributed services, code review culture. You learn from engineers actively shipping production code, not from a textbook.
Syllabus
Six modules to ship OpenSpec on a real production codebase — from npm install to a team running spec-gated CI:
- 1 Module 1: Install & bootstrap — openspec init, the AGENTS.md and project.md contract, choosing your AI tool (Claude Code / Cursor / Windsurf), writing a 200-line project.md that doesn't drift
- 2 Module 2: The proposal workflow — /opsx:propose end-to-end, anatomy of proposal.md + design.md + tasks.md, what makes a good proposal vs a shallow one, reviewing what the agent generated
- 3 Module 3: Validation & spec deltas — openspec validate, GIVEN/WHEN/THEN syntax, ADDED/MODIFIED/REMOVED deltas, CI integration; wiring validation as a blocking step on day one
- 4 Module 4: Implementation & review — /opsx:apply, reviewing the spec delta vs the code diff, when to override the agent, model selection for propose/apply/validate (Opus 4.7, Codex 5.5, cheaper tiers)
- 5 Module 5: Brownfield retrofitting — reverse-engineering specs from legacy code, the descriptive pass vs the prescriptive pass, human-in-the-loop second pass, retrofitting a real legacy module you didn't write
- 6 Module 6: Production rituals — team adoption, the archive as immutable history, telemetry opt-out, multi-engineer change isolation, post-archive analytics, recognising when OpenSpec is the wrong tool for the job
Prerequisites
Strongly recommended: SDD Foundations (#28) for the methodology and Claude Code Mastery (#26) for the agentic-coding daily loop. Claude Agent SDK (#27) is also a strong fit.
Solid daily workflow with an agentic coding tool (Claude Code, Cursor, or similar). Comfort with the CLI, Node.js basics, and Git Flow. A real codebase you can apply OpenSpec to.
What you'll build
You leave with OpenSpec running on a brownfield codebase you own, a spec-gated CI pipeline that blocks bad changes, and the team rituals that make spec-driven engineering stick past the honeymoon phase.
- OpenSpec install, init, project.md and AGENTS.md
- Slash commands: /opsx:propose, /opsx:apply, /opsx:archive
- openspec validate and CI integration
- Brownfield retrofitting: descriptive vs prescriptive specs
- Multi-engineer collaboration and change isolation
Where this fits in your career
Read alongside this course
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First lesson on us. Decide after meeting your instructor.
Sit in on the first session. If after lesson 1 you decide the instructor isn't the right fit, you don't pay for it — and no awkward conversation. (Trial offer applies to courses with more than 5 lessons; this one qualifies.)
Pricing & what's included
What's included
- 12 live sessions × 2 hours each — taught by the instructor, not a recording playback
- Slide deck for every session — yours to keep and refer back to
- Working code files and any data files used in class — cloned to your machine
- Weekly homework with personal code review from the instructor
- Recording on request — give the teacher a heads-up ("can't make Tuesday, please record it") and the session is recorded for you
Frequently asked questions
How much time per week will this take?
Plan for the live sessions plus roughly 1.5–2 hours of practice per session. Most students who finish on schedule put in 4–6 hours a week total. If you put in less, you still finish — it just takes longer.
What if I miss a class?
Tell the teacher BEFORE the session — "I can't make Tuesday, please record it" — and the teacher records that lesson and sends it to you. Recordings aren't a default catch-up archive; they're produced on request when you give a heads-up. After the lesson you do the homework, bring questions to the next session.
What's included in the price?
Live sessions with the teacher; the slide deck for each session (yours to keep); the working code files and any data files used in class; weekly homework with code review; and recordings of the sessions you give advance notice for. Anything beyond that — a certificate, alumni access, mock interviews — is listed explicitly in "What's included" above the FAQ for the courses where it applies.
What if I sign up and the teacher isn't a fit?
For courses with more than 5 lessons, the first session is effectively a trial — if after lesson 1 you decide the teacher isn't a fit, you don't pay for it. We'd rather you walk away after one lesson than push through 9 weeks of bad chemistry. (Courses with 5 or fewer lessons are short enough that the standard pricing applies — the trial offer doesn't make sense at that length.)
Can I get a refund partway through?
Yes. Within 14 calendar days of purchase you can withdraw and get a full refund on request, no reason needed — that's your statutory right under Georgian consumer-protection law. On top of that, our own guarantee: if you've attended fewer than 3 lessons, we refund in full with no deductions. Refunds go back to your original payment method within 14 days.
Can I switch the language of instruction?
The live sessions run in the language listed under "Available Languages" above. Slides and code files are typically available in all four (English, Russian, Ukrainian, Georgian). Many students attend sessions in one language and read materials in another — that's normal.
Will I be ready for a real job after this course?
One course rarely gets anyone hired by itself — for any field. What this course gives you is the foundation a junior hiring manager expects: working code you wrote yourself, the vocabulary to read other people's code, and the practice habits that make you employable. The honest answer to "am I ready?" is on our roadmap (link in the page header) — open the level you want to reach and read the "You're ready when" checklist.
Can I pay in instalments?
Yes for courses with a "Monthly Payment" option in the at-a-glance ribbon — usually two or three equal monthly payments. Courses without that option are paid in one go. If the price is the blocker, write to us — we look at every case.
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