DUCAT’SBitcoin GuildFollow one payment from selected UTXOs through exact serialization, authorization, relay policy, fee competition, block inclusion and possible replacement or reorganization. Every specialist lesson below contributes one part of the same state transition.
Each specialist lesson expands one relationship in this end-to-end map.
Every input names an exact prior transaction output and spends it whole.
Payment and change become new amounts locked to new scripts.
Version, vectors, scripts, witness and locktime become canonical bytes.
Each witness satisfies the previous output's locking condition for this transaction.
Nodes apply consensus preconditions and local mempool policy before forwarding.
A valid block spends old UTXOs and creates the new ones atomically.
You will be able to construct, decode, price and debug a transaction and explain txid, wtxid, RBF, CPFP, policy and confirmation risk.
Predict first, execute exact bytes or rules, then change one input and inspect the first failed boundary.
Serialize one input, two outputs, ScriptSig, ScriptPubKeys, witness, sequence, and locktime. Then decode the exact bytes, calculate the fee, and compare txid with wtxid after a witness change.
Use real learner input rather than a prewritten answer. Every result is calculated locally from the fields shown and invalid data fails closed.
Reverse complete hexadecimal bytes without reversing the characters inside each byte.
Change any field, predict what should change, then run the utility.
Safety boundary: This learning surface does not store inputs. Never paste a live seed phrase, private key, wallet backup, or confidential transaction.
Start at the top for a guided route, or open any lesson directly.
A UTXO is a specific unspent transaction output; transactions consume whole outputs and create new ones.
Teach, predict, run, explainInputs reference prior outpoints and provide witnesses; outputs assign values to new locking conditions.
Teach, predict, run, explainVersion, vectors, scripts, sequence, witness, and locktime serialize deterministically; txid and wtxid commit to different data.
Teach, predict, run, explainFees equal inputs minus outputs, while feerates use virtual size derived from transaction weight.
Teach, predict, run, explainWallets trade off fees, privacy, change, consolidation, and future spending cost when selecting UTXOs.
Teach, predict, run, explainNodes can reject relay or mining of a consensus-valid transaction under local policy without making it invalid forever.
Teach, predict, run, explainConfirmations measure accumulated proof of work after inclusion; required depth depends on value, threat model, and protocol configuration.
Teach, predict, run, explainReplace-by-fee uses sequence and mempool rules to replace an unconfirmed transaction with a higher-fee conflict.
Teach, predict, run, explainA child can pay enough fee for miners to include a low-fee parent when the package feerate is attractive.
Teach, predict, run, explainnLockTime, sequence, CLTV, and CSV constrain when transactions or spending paths become valid.
Teach, predict, run, explainDecode outpoints, ScriptSig, sequence, amounts, ScriptPubKeys, CompactSize lengths, and locktime directly from serialized transaction bytes.
Teach, predict, run, explainTrace witness serialization, txid versus wtxid, the coinbase witness reserved value, and the witness commitment that binds SegWit data into a block.
Teach, predict, run, explainFollow admission, relay, conflicts, RBF replacement, block connection, reorg reconsideration, expiry, size eviction, and local policy differences.
Teach, predict, run, explainThese distinctions stop the most consequential mistakes in this topic.