Whetstone.
The Whetstone catalog

Learn it properly. Once.

Crash courses and deep dives built for understanding - not for the algorithm. Read, build, and actually remember it.

Certification track

LangChain cert (LCAE)

Start here for the LangChain cert

LangChain Foundations

The create_agent harness end to end, mirroring the official Introduction to LangChain course that half the Build section is drawn from.

buildingagentsmiddleware
16 courses
CA
anthropicIntermediate

Claude Agents and Tools

The two CCDV-F domains that are really one question: what runs the loop, and what can it reach?

10 lessons233 min
CA
claudeIntermediate

Claude API Foundations

The two heaviest CCDV-F domains, which between them are half the exam, taught around the numbers that actually get asked.

15 lessons364 min
PC
promptingIntermediate

Prompt, Context and Safety on Claude

The 25% of CCDV-F that lives in the prompt, the window, the 400s and the guardrails.

10 lessons238 min
DD
dddIntermediate

Domain-driven design, the Fusion way

Learn DDD from zero, then write C# the team accepts on the first review.

26 lessons317 min
CA
csharpBeginner

C# and .NET, from the ground up

Cross from TypeScript to C# and write backend code that clears review the first time.

27 lessons342 min
LG
langchainIntermediate

LangGraph Ground School

LangChain, LangGraph, and LangSmith, learned by shipping real improvements to the systems you already love.

18 lessons900 min
DA
langchainIntermediate

Deep Agents Foundations

The deepagents harness end to end, mirroring the official LangChain Academy course lesson for lesson.

18 lessons304 min
LD
langgraphIntermediate

LangSmith Deployment

Deploy your agents to the cloud, connect to them, give them memory, and keep tenants out of each other's data.

19 lessons312 min
LF
langchainIntermediate

LangChain Foundations

The create_agent harness end to end, mirroring the official Introduction to LangChain course that half the Build section is drawn from.

16 lessons240 min
LM
lcaeIntermediate

LCAE Mock Exam

A timed, exam-shaped rehearsal for the LangChain Certified Agent Engineer exam.

4 lessons120 min
LM
lcaeIntermediate

LCAE Mock Exam B

A second timed, exam-shaped rehearsal for the LangChain Certified Agent Engineer exam.

4 lessons120 min
LM
lcaeIntermediate

LCAE Mock Exam C

A third timed, exam-shaped rehearsal for the LangChain Certified Agent Engineer exam.

4 lessons120 min
AO
langsmithIntermediate

Agent Observability and Evaluation

See the agent, then measure it. The whole Test quarter of the LCAE, in the order the official course teaches it.

16 lessons244 min
PM
langsmithIntermediate

Production Monitoring for AI Agents with LangSmith

Cost, product analytics, quality, security. The 25% of LCAE that lives in the LangSmith UI rather than in your editor.

17 lessons257 min
MP
pythonBeginner

Modern Python for a TypeScript Developer

You already know how to program. This is the spelling, the 2026 toolchain, and the handful of places Python genuinely disagrees with you.

13 lessons194 min
ZF
terminalBeginner

Zellij, from the ground up

Drive your terminal by muscle memory, not menus.

20 lessons204 min