Software Engineer · Building AI/LLM, Data, and Search-Driven Products · Founder @ aVenture.vc.
- Building aVenture.vc – early-stage startup company research & intelligence platform
- Improving multi-source enrichment agents for structured company + document profiles
- Iterating on hybrid web search + conversational reasoning (Researchly)
- Experimenting with a modern web application using AI to anticipate user needs (Composer)
| Project | What It Is | Stack / Notes | Link |
|---|---|---|---|
| aVenture | Intelligence + diligence platform for venture research | Multi-service web app, enrichment agents | aVenture.vc |
| aVenture: TUI Company Search | Terminal-first research interface | Rich TUI, streaming updates | tui.aventure.vc |
| TUI4J | A modern terminal user interface library for Java | Java, Spring a port of BubbleTea from Go | GitHub |
| Researchly | Perplexity-like agentic deep web search chat (previously SearchAI) | RAG, SERP + crawler fusion | GitHub |
| williamcallahan.com | Writing, background, bookmarks | Next.js, S3, TypeScript | GitHub |
| Composer | AI-assisted email application | Java 25, Spring Boot 3.5, Svelte 5 | GitHub |
| Brief | A beautiful terminal user interface LLM client for AI chat with tool calls and model switching | Java 25 | GitHub |
| Repo Tokens Calculator | Quickly estimate token + embedding budgets for repos | Parsing + language-aware heuristics | GitHub |
| Filey: VS Code Extension | Flags deprecated files in large workspaces | Developer experience tooling | GitHub |
| findmybook | Millions of books searchable with semantic + structured filters | Indexing + metadata normalization | GitHub |
Core Toolbox:TypeScript / JavaScript · Java · Python · Node.js / Bun / Deno · React / Next.js / Svelte / SvelteKit · PostgreSQL / MySQL · Spring Boot · Vector Embeddings / Qdrant / pgvector · Playwright / Scraping · LLMs (OpenAI, Anthropic, Qwen, LLama, DeepSeek, etc.)
These days I'm doing a lot of work on:
- Multi-stage web crawling → parsing → enrichment data pipelines
- Hybrid retrieval (BM25 + dense + rerankers)
- Streaming data/UX patterns
If you're working on similar things, feel free to reach out! Especially if you're in SF.
I live in the United States. Grew up in a small town in Iowa, and am now living my dream of building tech in San Francisco. I post and share regularly at:
- Personal writing: williamcallahan.com
- Live bookmarks feed: williamcallahan.com/bookmarks
- Venture capital/angel investments: williamcallahan.com/investments
DM on X or connect on LinkedIn.