deanonymizer is a command-line system for defensive OSINT exposure measurement. It estimates re-identification risk from public Reddit and Hacker News corpora (now supports web, GitHub & StackOverflow too!) by aggregating weak signals, scoring identity hypotheses, and emitting evidence-linked remediation guidance.

The design follows the inference setting discussed in:

• arXiv:2602.16800

Operational premise: low-entropy disclosures that appear non-identifying in isolation may become identifying under cross-post and cross-platform fusion.

Given a subject handle set H and public artifact set D, produce a risk report R containing:

• identity-relevant feature extractions
• evidence-backed linkage claims
• calibrated confidence labels
• prioritized mitigation actions

• Observer model: passive adversary with access to publicly available text and metadata only
• Data boundary: no private APIs, credentialed access, or hidden datasets
• Attack primitive: probabilistic entity linkage via feature composition
• Security goal: minimize attributable identity surface from public traces

1. Acquisition
   • Reddit artifacts from Arctic Shift API
   • Hacker News artifacts from HN Algolia Search API
   • GitHub profile fields + public events (commits, issues, PRs, review comments) via the GitHub REST API; commit author name and email from PushEvent payloads are folded in inline. Optional GITHUB_TOKEN raises the rate limit.
   • Stack Overflow answers, questions, comments, and profile fields via the Stack Exchange API v2.3
   • Shallow link-follower for any external website declared in a GitHub or Stack Overflow profile: fetches the root page, then up to 5 same-origin sub-paths prioritized by identity-shaped routes (/about, /cv, /resume, /contact, /bio, /me, /portfolio, …). Preserves mailto: and http(s):// href values before HTML stripping so contact emails behind a link survive.
2. Canonicalization
   • Heterogeneous source records mapped into a unified item schema
   • Temporal and textual normalization for bounded-context inference
3. Feature extraction and attribution
   • LLM pass: detection of location, affiliation, temporal routine, self-disclosed demographics, cross-platform handles, external URLs, and stylometric cues, with attribution binding from each claim to quote-level evidence and permalink
   • Deterministic regex pass that runs in parallel and bypasses the model: extracts emails (with [at] / [dot] obfuscation handling) and cross-platform social handles for LinkedIn, Twitter/X, GitHub, YouTube, Instagram, Bluesky, Reddit, Hacker News, Telegram, GitLab, Stack Overflow, and Mastodon from URL patterns in the corpus. False-positive paths like twitter.com/home are filtered and the audited account itself is excluded.
4. Risk synthesis
   • Confidence-calibrated findings: low, medium, high
   • Explicit exact-user section and public proof URL set
   • Direct-identifier block (emails + discovered handles) rendered before the LLM findings, so concrete leaks always appear regardless of how the model chose to summarize them
   • Finding-level remediation recommendations

• Human-readable report with ranked findings and rationale, grouped by confidence (high → medium → low)
• Dedicated direct identifiers extracted block surfacing emails and cross-platform handles found by the deterministic regex pass
• JSON serialization for longitudinal tracking and downstream analytics; AuditResult.directIdentifiers exposes the raw email + social handle hits alongside the model findings
• Optional strict validation: fail if no external proof URL exists beyond audited platform profile endpoints

npm install

The analysis stage runs on any of three interchangeable backends, selected automatically from the environment (override with --provider):

Anthropic (native, default when only this key is set)

export ANTHROPIC_API_KEY=sk-ant-...
# default model is the fast claude-haiku-4-5
# optional: export ANTHROPIC_MODEL=claude-sonnet-4-6  # slower, higher quality

Any OpenAI-compatible endpoint — OpenAI, Google Gemini, Ollama, Groq, Together, etc. Point OPENAI_BASE_URL at the provider's Chat Completions surface:

# OpenAI
export OPENAI_API_KEY=sk-...
export OPENAI_MODEL=gpt-4o-mini

# Google Gemini (OpenAI-compatible endpoint)
export OPENAI_API_KEY=...your-gemini-key...
export OPENAI_BASE_URL=https://generativelanguage.googleapis.com/v1beta/openai/
export OPENAI_MODEL=gemini-2.0-flash

# Ollama (local, no key required)
export OPENAI_BASE_URL=http://localhost:11434/v1
export OPENAI_MODEL=llama3

Claude Code CLI (no API key) — routes the analysis through your existing Claude Code session by shelling out to claude -p, so no ANTHROPIC_API_KEY is needed. Select it explicitly:

npm run audit -- my_reddit_handle --provider claude-code
# optional: pin the model or point at a non-default CLI binary
export CLAUDE_CODE_MODEL=claude-sonnet-4-6
export CLAUDE_CODE_BIN=/path/to/claude

Tradeoffs vs. the native Anthropic SDK path: no prompt caching, no max_tokens control, and slower per-call startup (CLI cold start), so it is opt-in rather than auto-detected. The JSON-repair fallback covers the lack of a response_format: json_object equivalent.

Selection order: --provider flag → LLM_PROVIDER env → auto-detect (OPENAI_* / --base-url → openai; ANTHROPIC_API_KEY → anthropic). claude-code is never auto-detected — request it via --provider claude-code or LLM_PROVIDER=claude-code. Existing Anthropic-only setups keep working unchanged. Native Anthropic prompt caching is preserved on the Anthropic path; the OpenAI path requests response_format: json_object where supported and still runs the JSON-repair fallback for endpoints that ignore it.

# Reddit only
npm run audit -- my_reddit_handle

# Reddit + Hacker News
npm run audit -- my_reddit_handle --hn my_hn_handle

# Hacker News only
npm run audit -- --hn my_hn_handle

# GitHub only (also follows the linked website + sub-pages)
npm run audit -- --github my_gh_handle

# Stack Overflow only (accepts numeric user_id or profile URL)
npm run audit -- --so 1234567

# All four platforms at once — cross-platform handle correlation is the
# strongest signal the analyzer can flag
npm run audit -- my_reddit_handle --hn my_hn_handle --github my_gh_handle --so 1234567

# Audit through the Claude Code CLI (no API key needed)
npm run audit -- my_reddit_handle --provider claude-code

# JSON output
npm run audit -- my_reddit_handle --json -o report.json

# Strict proof validation
npm run audit -- my_reddit_handle --require-external-proof

# Faster wall-clock analysis (parallel chunk workers)
npm run audit -- my_reddit_handle --concurrency 3

# Run against a local Ollama model
npm run audit -- my_reddit_handle --base-url http://localhost:11434/v1 --model llama3

# Force a specific provider/model for one run
npm run audit -- my_reddit_handle --provider openai --model gpt-4o-mini

• Increase -n to expand retrieval depth
• Increase --max-chars to reduce context truncation
• Pin the model (ANTHROPIC_MODEL / OPENAI_MODEL / CLAUDE_CODE_MODEL / --model) to control inference backend variance
• Store JSON outputs for temporal diff and regression analysis

npm run build

A GitHub Actions workflow at .github/workflows/ci.yml runs npm run lint, npm run format:check, tsc --noEmit, npm test, and npm run build on every push and pull request against main, across a Node 20 / 22 / 24 matrix.

• Findings are probabilistic and should not be interpreted as identity proof
• Recall is upper-bounded by source completeness and truncation constraints
• Stylometric separability is population- and domain-dependent
• Confidence calibration depends on evidence density and artifact quality
• GitHub's public events feed is capped at roughly 300 events from the last 90 days, so commit author emails that only appear in older history won't be picked up unless you supply GITHUB_TOKEN and walk repos directly (not yet implemented)
• The website link-follower is single-hop with same-origin sub-page expansion; JavaScript-rendered SPAs (Next.js client-rendered, Notion exports, etc.) return mostly empty bodies because there is no headless browser in the pipeline
• @users.noreply.github.com addresses are filtered out of the direct identifier extractor since they are the privacy-preserving default rather than a leak