Every Bitcoin builder needs a reliable local environment before touching protocol code. Think of this lesson as preparing a workshop: if your tools are missing or half-configured, every later lesson becomes frustrating noise.
Why this matters
Bitcoin software is unforgiving. A broken Node install, an old OpenSSL, or no way to run regtest (a private local chain) will block wallets, explorers, and Lightning labs. Getting the toolchain right once pays off for months.
Analogy
Setting up for Bitcoin development is like packing for a multi-day hike. You do not need every gadget in the store, you need the few tools you will actually use daily, verified before you leave the trailhead.
Choose your stack
Most Pull lessons assume you can run a modern JavaScript or Rust toolchain. Pick one primary language for app code, but keep both runtimes available for ecosystem tooling.