Settings

Settings live in cdk/settings.py and the per-collection env files (.env_hcho / .env_no2, plus the gitignored .env.local; samples: .env.sample, .env.local.sample). The ones that matter most:

Setting	Default	Meaning
TEMPO_COLLECTION	—	hcho or no2; one deployment per collection
ICECHUNK_BUCKET	—	existing bucket for the store; must be in the stack's region (checked at deploy)
ICECHUNK_BUCKET_NAME	—	bucket to create when ICECHUNK_BUCKET is unset
S3_PREFIX	—	common key prefix for all pipeline output (run artifacts land at <S3_PREFIX>/backfill/); per collection, since every IAM grant is scoped under it
ICECHUNK_PREFIX	—	the repository's key prefix, relative to S3_PREFIX
INVENTORY_PREFIX	<S3_PREFIX>/inventory	key prefix the backfill partition Lambda may read inventories from
DATA_BUCKET_NAME	—	source bucket workers read granules from
BACKFILL_ENABLED	false	deploy the backfill Step Functions pipeline
BACKFILL_PARTITION_SIZE	500	files per partition (one merged commit each)
BACKFILL_MAX_ITEMS_PER_BATCH	10	files per worker Lambda invocation
BACKFILL_MAX_CONCURRENCY	50	parallel workers per partition
FORWARD_QUEUE_ENABLED	inverse of backfill	enable the SQS consumer
SQS_BATCH_SIZE	10	files per consumer invocation (one commit each)
POLL_SCHEDULE_MINUTES	30	CMR poller cadence
POLL_START_ISO	—	first-poll start time (else a fixed lookback from now); set to the backfill inventory's build time when enabling forward processing
RESORT_SCHEDULE_HOURS	24	re-sort job cadence
RESORT_MAX_FOLD	500	max pending granules parsed per re-sort run
EARTHDATA_SECRET_ARN	—	Secrets Manager secret with EDL credentials for source reads
GARBAGE_COLLECTION_FREQUENCY	—	days between Icechunk GC runs (needs VPC_ID)
GC_EXPIRY_DAYS	30	snapshot expiry for GC runs — also the store's rollback window
ALARM_EMAIL	—	notification email for all alarms (see Monitoring)
OWNER	—	Owner cost-allocation tag on every resource; unset applies no tag
CLIENT	—	Client cost-allocation tag on every resource; unset applies no tag

The Lambda images install against lambda/constraints.txt, an export of the repo's uv.lock, so deploys run the dependency versions the test suite ran. Regenerate it with the command in its header whenever the lock changes.

Concurrent backfill runs are not supported.