Scramjet Proxy ~repack~ Link

Here’s a solid, technical write-up on Scramjet Proxy — suitable for a developer documentation portal, a GitHub README, or a technical blog post.

Common Pitfalls and Solutions

Pitfall: The Scramjet Proxy uses too much CPU. Solution: Reduce maxParallel and add a setTimeout delay of 10ms inside the map function to prevent event loop starvation. scramjet proxy

Pitfall: Proxies die mid-stream. Solution: Implement a .filter() that checks for HTTP error codes and re-routes dead proxies to a .catch() stream that removes them from the active list. Here’s a solid, technical write-up on Scramjet Proxy

Pitfall: Memory leak with large HTML responses. Solution: Use Scramjet’s StringStream and .split() to process the response chunk by chunk rather than storing the entire HTML string. Common Pitfalls and Solutions Pitfall: The Scramjet Proxy

Key Features of a Scramjet Proxy

Installation

npm install @scramjet/proxy
# or
yarn add @scramjet/proxy

4. Building a Minimal Scramjet Proxy (Linux, XDP)

We'll use eXpress Data Path (XDP) + BPF for kernel‑bypass speed.

7. Security and Hardening

• Default deny-all routing, explicit allow-lists, and rate-limiting per-identity.
• Offload secrets management to dedicated vaults; avoid storing TLS private keys in worker memory unencrypted.
• Use WASM sandboxes or process isolation for plugins; enforce CPU/memory/time quotas.
• Regularly rotate certificates and enforce minimum TLS versions and strong cipher suites.

Typical use cases

• API edge proxy for mobile apps to minimize tail latency.
• CDN fronting for dynamic content where CPU and memory are constrained.
• IoT gateways aggregating many short-lived device connections.
• Sidecar proxy in microservice environments needing minimal overhead.

14. Bibliography and Further Reading (topics to search)

• Materials on zero-copy I/O (splice, sendfile, io_uring).
• eBPF/XDP and AF_XDP design patterns.
• WASM for edge compute and plugin sandboxes.
• QUIC and WebTransport protocol design papers.
• Case studies of high-performance proxies (Envoy, Nginx, HAProxy, Seastar).

Example: VPP Scramjet Plugin (Minimal)

-- scramjet.lua for VPP
function scramjet_inline(data)
    local payload = data:get_offset(42) -- skip eth+ip+tcp
    if payload:find("USER") then
        payload:gsub("USER", "X-USER")  -- mutate
        data:update_checksums()
    end
    return data
end
-- Register as inline service
vpp.register_node("scramjet", scramjet_inline, priority=inline)