Can you actually leave? We tested it on mainnet: forced a 100k sat Blink wallet out of Spark, back onto Bitcoin. No operators, just the seed and a saved recovery bundle. Costs, lessons, code and txIDs onchain:

Case study: a real Spark unilateral exit on Bitcoin mainnet

Recovering 100k sats with seed and state backups.

Trust model reiterated. In-app exit next.

Correction: "seed only, no operators" compressed two steps. The leaf data (recovery bundle) must be fetched while operators are online. The exit itself then needs nothing from them: seed + saved bundle is the accurate claim. Full mechanics and costs:

GitHub

spark-unilateral-exit/docs/mainnet-exit-case-study.md at main · blinkbitcoin/spark-unilateral-exit

Tools and guide for Spark unilateral-exit recovery - blinkbitcoin/spark-unilateral-exit

I just force-exited a non-custodial Blink wallet (using Spark) on Bitcoin mainnet. Seed only - no operator cooperation: recovery bundle, fee funding, CPFP signing and sweep all derived from the wallet seed. The honest numbers for a 100k sat wallet: • 22 leaves, 253 tx packages to exit fully • only 4 leaves (90% of the value) were worth exiting - fees would have eaten the other18 • ~9.4k sats in fees to recover 90.1k, one package per block per chain, then a ~2-week timelock Non-custodial means you can always leave. But the fire escape is narrow - full case study with costs, failures and lessons:

GitHub

spark-unilateral-exit/docs/mainnet-exit-case-study.md at main · blinkbitcoin/spark-unilateral-exit

Tools and guide for Spark unilateral-exit recovery - blinkbitcoin/spark-unilateral-exit