Live Requests — Native Servers

Covers servers written in C, C++, Rust, Go and other compiled languages — including ones whose source you do not have, such as a stock nginx.

How this differs from the other languages

Python, Ruby, PHP, JavaScript and Elixir all publish request spans from a middleware layer inside the recorded process. A native server has no such seam: there is no standard middleware interface to hook, and the server may not be code you can modify at all.

So CodeTracer takes a different route. A supervisor discovers the requests from the recording itself, rather than the server announcing them. You do not need to link a library, recompile, or patch the binary.

Record your server

ct record --server -o ./trace -- nginx -g 'daemon off;'

or your own binary:

ct record --server -o ./trace -- ./my-service --listen 127.0.0.1:8080

Flags after the program name are passed through unchanged. The server must run in the foreground — for daemons, use whatever flag keeps them attached (-g 'daemon off;' for nginx, --nodaemonize and similar elsewhere), so that stopping the recording with Ctrl-C stops the server too.

Watch requests arrive

In a second terminal:

ct replay -t ./trace

Send traffic and rows appear as requests are discovered.

Open a recording later

ct replay ./trace

What gets recorded

• **Method, path, status and duration** per request.
• The **position in the recording** where each request was served, so

double-clicking a row seeks there.

Route *templates* are generally not available: without framework knowledge there is nothing that says /users/7 and /users/9 are the same endpoint. Rows are labelled with the concrete path instead.

Requirements

Linux or macOS. Recording a native program uses CodeTracer's native recording backend, which needs no changes to the program under test.