ProxyCaching

Stop waiting for the same API call. Again.

A local HTTP/HTTPS caching proxy for developers — first request hits the real API,
every next identical request is served from local cache instantly.

Get started · Examples · Configuration · Admin UI · Report a bug

Every developer knows the pain:

• Slow external APIs making every test run take forever
• Paid API quotas burning through during development (OpenAI, Stripe, etc.)
• Flaky or rate-limited services breaking your local workflow
• Same request, hundredth time — because you restarted the dev server again

proxycaching sits between your app and the internet. First call goes through normally. Every identical call after that? Served from local cache in milliseconds — no network, no cost, no waiting.

• HTTP & HTTPS caching — full MITM support for HTTPS traffic
• Disk-backed cache — persists between restarts, readable only on your machine
• Rule engine — cache only what you want (by domain, path, method, and more)
• Admin UI — browser-based panel to inspect cached requests, hit counts, and timestamps
• Encryption — optional on-disk encryption for cached responses
• Zero config to start — sensible defaults, configure only what you need

npm install
npm run build
npm run start

That's it. Your caching proxy is running on :8080 and the admin UI is on :8081.

Test it:

# First call — hits the real API
curl --proxy http://localhost:8080 https://api.example.com/data

# Second call — served from cache instantly ⚡
curl --proxy http://localhost:8080 https://api.example.com/data

Open the admin UI to see what was cached: http://localhost:8081

Real-world usage examples are in the /examples directory:

The built-in admin panel lets you:

• Browse all cached requests with timestamps and hit counts
• Inspect request and response details for each cached entry
• Manage cache rules in real time with rule editors and grouping options
• View proxy health at a glance with status cards and cache metrics
• Export or install the MITM CA certificate

The new admin UI includes:

• A modern dashboard with server status, uptime, cache entries, cache size, and MITM CA controls
• Tabbed views for the cache store and cache rules
• Search and refresh controls for the cache store list
• Cache entry details modal showing request headers, request body, response metadata, hit count, and delete action
• Rule editor modal for creating and updating rules by method, domain, path, headers, query params, and body pattern

Cache Store View

The main cache store screen shows all cached request keys with method, URL, hit count, and last access time. Use the search field and refresh button to quickly locate entries.

Cache Entry Details

Click any cache row to open a detailed modal with request headers, request body, response metadata, hit count, and a delete action.

Cache Rules View

The rules list displays active cache rules, including method, domain, paths, header filters, query filters, and grouping mode.

Cache Rule Editor

The editor modal allows fine-grained rule creation and updates with method selection, domain/path matching, required headers, query parameters, and body pattern support.

Available at http://localhost:8081 when proxy.adminEnabled is true.

Configure via config/config.json. All settings are optional — defaults work out of the box.

{
  "proxy": {
    "port": 8080,
    "adminPort": 8081,
    "adminEnabled": true,
    "mitmEnabled": false,
    "podcachePath": "config/podcache",
    "encryption": {},
    "logging": {
      "level": "info"
    }
  }
}

By default, HTTPS traffic is proxied as an opaque tunnel and not cached. To cache HTTPS:

1. Set proxy.mitmEnabled: true in config/config.json
2. Start the proxy — it will generate a local CA certificate under config/mitm/proxy-ca/
3. Install the CA certificate into your OS trust store (or use the Admin UI → CA Install)
4. Restart your browser or HTTP client

# Or install via Admin API
curl -X POST http://localhost:8081/ca-install

For scripting and automation:

Run directly from TypeScript source (no build step needed):

npm run dev

Free for personal and open-source use. Commercial use (any for-profit company, even internal tools) requires a paid license.

→ Read the full license → Commercial licensing: proxycaching@interia.pl