diff --git a/README.md b/README.md
index ff2c9dc..29e75cf 100644
--- a/README.md
+++ b/README.md
@@ -19,14 +19,10 @@ rails db:migrate
 ## Run
 
 ```
-rails db:reset && ./doc/poc.rb
+rails s
 ```
 
-Result is GraphViz dot
-
-Put it to <https://dreampuf.github.io/GraphvizOnline/> to visualize
-
-benchmarks
+## DB Benchmark
 
 ```
 RAILS_ENV=production bundle exec rake benchmark:bm NUM=500
@@ -34,24 +30,6 @@ RAILS_ENV=production bundle exec rake benchmark:bm NUM=500
 RAILS_ENV=production bundle exec rake benchmark:bm NUM=5000 BATCH=100
 ```
 
-## Showcase
-
-- [db/migrate](db/migrate)
-- [doc/poc.rb](doc/poc.rb)
-
-## References
-
-- https://blog.ethereum.org/2015/11/15/merkling-in-ethereum
-- https://transparency.dev/verifiable-data-structures/
-- https://transparency.dev/how-to-design-a-verifiable-system/
-- https://github.com/google/trillian/tree/master/merkle
-- https://github.com/google/trillian/tree/master/log
-- https://github.com/transparency-dev/formats/blob/main/log/README.md#checkpoint-format
-- https://github.com/transparency-dev
-- https://datatracker.ietf.org/doc/html/rfc9162#name-merkle-trees
-- https://aly.arriqaaq.com/merkle-tree-and-verifiable-data-structures/
-- https://github.com/mpalmer/merkle-hash-tree
-- https://www.derpturkey.com/merkle-tree-construction-and-proof-of-inclusion/
-- https://github.com/OpenZeppelin/merkle-tree
-- https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/cryptography/MerkleProof.sol
-- https://medium.com/@colbyserpa/nostr-2-0-layer-2-off-chain-data-storage-b7d299078c60
+## License
+
+Apache 2.0