Two weeks ago, spectr-ai and AbiLens didn't exist. Today, spectr-ai is a working AI smart contract auditor with a CLI engine and a Next.js web interface. AbiLens lets you chat with any deployed EVM smart contract by address. Both use multiple LLM providers, both have test suites, and both solve real problems I actually had. Here's what I learned building them. 1. Start with the CLI, Add the Web UI Later Both projects started as command-line tools. spectr-ai began as a Node.js script that took a Solidity file path, sent it to Claude, and printed the audit report. AbiLens started as a terminal chat loop that resolved contract ABIs and let me call read functions. The CLI-first approach forced me to get the core logic right before worrying about layout, state management, or component architecture. The engine module in spectr-ai is completely independent of the web layer — it exports functions that accept a file path and options and return structured results.…