Claude API developer for production apps and agents
I hold Anthropic’s Claude Certified Developer – Foundations credential, scored 896/1000 on a proctored exam in September 2026, and Claude already runs in products I have built. I integrate it with structured outputs, prompt guardrails, careful context engineering and evals, so the code that consumes its answers can trust them.
- Claude Certified Developer – Foundations
- 896/1000 on a proctored exam
- Valid to Sep 2027, verifiable on Credly
What the Claude certification covers
Claude Certified Developer – Foundations is Anthropic’s proctored exam for building, integrating and shipping production apps and agents on Claude, using the Claude API, Claude Code, custom tools and MCP servers. The pass mark is 720 out of 1000; I scored 896. The credential is valid through September 2027 and can be checked on Credly, which lists the skills it assesses.
- Claude API integration and prompt engineering
- Context engineering and model optimization
- Agent development and MCP server development
- Eval and debugging
- Application security
Claude in production, not just in demos
The certification confirms work I was already shipping. Claude sits inside products I have built, each with its own job and its own way of failing: coaching a user through a property deal, generating marketing content, or searching messy personal data. The approach is the same in each case: treat the model’s response as untrusted input until it has been checked.
- OnOffDeals: Claude as an in-app deal coach with prompt guardrails, structured output validation and adversarial red-teaming after deploy
- PowerSmith Energy: AI content tooling on the Anthropic SDK with structured outputs for blog generation and social artwork
- Life Search AI: on-device OCR, including Hindi Devanagari, plus Claude for natural-language search over screenshots, notes and documents
- Gurukin: a free Claude Certified Developer – Foundations prep track with 758 practice questions and a fresh 53-item mock exam every sitting
How I build with the Claude API
I define the output schema before writing the prompt, validate every response against it (Pydantic 2 on Python backends), and retry or fall back when validation fails. Context is engineered rather than stuffed: only the records, instructions and examples a call needs, which keeps answers sharper and token costs lower. Guardrails cover off-topic, unsafe and injected instructions. Each prompt or model change runs through an eval set first, and the Claude model is chosen per task for quality, latency and cost.
Rates from $20/hour
Hourly for open-ended work, fixed price for defined projects. The first call is free and there's no obligation.
Frequently asked questions
Can you add Claude to an app that already exists?
Yes. I often drop into codebases with no documentation: I reproduce the problem, isolate it and write up the cause before changing anything. I work across FastAPI, Django, Flask and Node.js backends with React or Next.js frontends, and wire Claude into your existing auth and data layer rather than bolting on a separate service.
Do you only build with Claude?
No. I also work with OpenAI and Google Gemini, and with open models through Ollama for local-first projects. I pick the model that fits the task, latency and budget, and I design the integration so that switching models later is a contained change rather than a rewrite.
How much does it cost to hire a Claude API developer?
Rates start from $20/hour. For a defined integration, such as a Claude-powered assistant or a structured extraction step, I quote a fixed price after a free intro call. Anthropic API usage is a separate cost that depends on volume, and careful context design keeps it lean.