What happens when PHP runs your code
A request walks from the SAPI to the Zend VM — lexing, compilation to opcodes, the OPcache lookup that skips both, and execution.
A technical publication about PHP
Understanding PHP below the abstraction.
A technical publication about PHP internals, performance, architecture, and production behavior — measurements over assumptions, trade-offs over rules.
opcache.opt_debug_level=0x20000PHP 8.5
readPlain:0000 CV0($o) = RECV 10001 T1 = FETCH_OBJ_R CV0($o) string("v")0002 RETURN T1readBacked:0000 CV0($o) = RECV 10001 T1 = FETCH_OBJ_R CV0($o) string("v")0002 RETURN T1readVirtual:0000 CV0($o) = RECV 10001 T1 = FETCH_OBJ_R CV0($o) string("v")0002 RETURN T1Latest posts
All posts
Five subjects
Every post belongs to one of them. Each subject has its own archive, newest first.
Internals
The engine: compilation, the Zend VM, memory layout, and the data structures behind the values you pass around.
Performance
Measurement: profiling, benchmark method, and optimization that arrives with a number attached.
Architecture
How an application is put together: boundaries, dependency injection, layering, and what a framework design costs later.
Runtime
Production behavior: PHP-FPM pools, worker processes, long-running runtimes, and where memory goes over a day.
Ecosystem
The tooling and standards around the language: Composer, static analysis, and the PSRs.
Series
Written to be read in order.
Each series builds one argument across several posts. Start at part one; every part links to the next.
Read in order