Debugging on tsvinc

Every Route Registered. Every Request 404'd.

Mon, 06 Jul 2026 00:00:00 +0000

Thirty-three routes registered. Startup log confirms it. The /routes management endpoint lists every one. And under load, every single request returns 404.

This is the reactive Micronaut branch of the space observatory benchmark — 28 upstream API calls, 10 HTTP clients, all pointed at a Go mock server that deliberately injects failures (HTTP 500, 504-after-delay, abrupt connection close). The imperative sibling branch works. The lighter synth variant works. This one: 100% 404.

Error Is Not Exception: Micrometer's Silent CPU Metric on Native Image

Mon, 22 Jun 2026 00:00:00 +0000

Part 13 in the Memory Benchmark series.

The catch block that catches nothing

This code has a bug. Not a typo, not a logic error. A type hierarchy bug.

private double invoke(@Nullable Method method) {
    try {
        return method != null
            ? toDouble((Number) method.invoke(operatingSystemBean))
            : Double.NaN;
    }
    catch (IllegalAccessException | IllegalArgumentException
           | InvocationTargetException e) {
        return Double.NaN;
    }
}

That’s micrometer’s ProcessorMetrics.invoke() (v1.16.5). It calls JMX methods via reflection, wraps the call in three catch clauses. Standard defensive coding.

The AOT Hang That Wasn't

Wed, 10 Jun 2026 00:00:00 +0000

One line in CLAUDE.md: “Micronaut AOT hangs native image — keep both false. AOT disabled.”

Five sessions. Five different engineers (all me, different days). Nobody questioned it. The line accreted authority through repetition, the way all project folklore does. Somebody hit a problem, wrote the workaround, moved on. The workaround became canon. Canon became architecture.

Time to look under the coat.

Three Bugs, One Trenchcoat

What I’d been calling “the AOT hang” was three separate failures happening in sequence. Fix one, hit the next. Each one looked identical from the outside: app starts, prints banner, nothing happens. The diagnosis “AOT breaks everything” was reasonable. It was also wrong three different ways.

Three Bugs in a Trenchcoat Pretending to Be One Hang

Sun, 07 Jun 2026 00:00:00 +0000

The CLAUDE.md for this project had a one-liner that persisted for a week: “Micronaut AOT hangs — keep disabled.”

Every developer who touched the project read that line, nodded, and moved on. AOT disabled. Property set to false. Life continued. Nobody questioned it because it was technically true — AOT had hung — and the project worked without it.

Then the benchmark numbers arrived. Non-heap at 119 MB. Container limit at 256 MB. JVM OOM-killing at 150 concurrent users. And a footnote in the Micronaut AOT docs: “build-time service loading reduces runtime metaspace by eliminating classpath scanning.”