Environment Variables

Mode Selection

Variable	Type	Description
VITIATE_FUZZ	1	Enables fuzzing mode. Each fuzz() call becomes a supervisor and enters the mutation-driven fuzz loop. Also set internally by the npx vitiate CLI.
VITIATE_OPTIMIZE	1	Enables corpus minimization mode. Replays all corpus entries, runs set cover, and deletes redundant cached entries.

When neither is set, fuzz() runs in regression mode - replaying saved corpus entries as test cases.

Configuration

Variable	Type	Description
VITIATE_FUZZ_TIME	integer	Total fuzzing time in seconds. Overrides fuzzTimeMs from code and -max_total_time from CLI.
VITIATE_FUZZ_EXECS	integer	Maximum fuzzing iterations. Overrides fuzzExecs from code and -runs from CLI.
VITIATE_DEBUG	1	Enable debug output (logs mode, coverage map size, and internal state).
VITIATE_MAX_CRASHES	integer	Maximum crashes to collect before stopping. Overrides maxCrashes from code.

Internal

These are set by Vitiate internally. Do not set them manually unless building a custom runner.

Variable	Type	Description
VITIATE_SUPERVISOR	1	Indicates the process is a supervised child worker. Set by the supervisor.
VITIATE_SHMEM	string	Shared memory handle for coverage map. Set by the supervisor.

Precedence

fuzz, regression, and optimize subcommands

Configuration is resolved in this order (highest priority first):

1. CLI flags (--fuzz-time, --fuzz-execs, --max-crashes)
2. Environment variables (VITIATE_FUZZ_TIME, VITIATE_FUZZ_EXECS, VITIATE_MAX_CRASHES)
3. Per-test FuzzOptions in code
4. Plugin-level fuzz defaults
5. Built-in defaults

libfuzzer subcommand

For the libFuzzer-compatible CLI, environment variables take highest priority to match libFuzzer conventions:

1. Environment variables (VITIATE_FUZZ_TIME, VITIATE_FUZZ_EXECS)
2. CLI flags (-max_total_time, -runs)
3. Per-test FuzzOptions in code
4. Plugin-level fuzz defaults
5. Built-in defaults