CRYSTAL-SPEC(1)  Crystal Compiler Command Line Reference Guide CRYSTAL-SPEC(1)

NAME
       crystal-spec - Compile and run Crystal spec files

SYNOPSIS
       crystal spec [options] [files]

OPTIONS
       -d, --debug
           Generate the output with symbolic debug symbols.  These are read
           when debugging the built program with tools like lldb, gdb,
           valgrind etc. and provide mappings to the original source code for
           those tools.

       --no-debug
           Generate the output without any symbolic debug symbols.

       -D FLAG, --define FLAG
           Define a compile-time flag. This is useful to conditionally define
           types, methods, or commands based on flags available at compile
           time. The default flags are from the target triple given with
           --target-triple  or the hosts default, if none is given.

       --error-trace
           Show full error trace.

       -O LEVEL
           Optimization mode: 0 (default), 1, 2, 3. See OPTIMIZATIONS for
           details.

       --release
           Compile in release mode. Equivalent to -O3 --single-module

       -s, --stats
           Print statistics about the different compiler stages for the
           current build. Output time and used memory for each compiler
           process.

       -p, --progress
           Print statistics about the progress for the current build.

       -t, --time
           Print statistics about the execution time.

       --no-color
           Disable colored output.

crystal 1.21.0                    2026-07-23                   CRYSTAL-SPEC(1)