> ## Documentation Index
> Fetch the complete documentation index at: https://base-a060aa97-docs-use-case-ia-overhaul.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Reconcile With Memos

> Tag stablecoin operations with an onchain reference so you can match them to offchain records at scale.

export const StablecoinDemo = ({flow}) => {
  const C = {
    blue: "var(--wf-blue)",
    onBlue: "var(--wf-on-blue)",
    cerulean: "var(--wf-cerulean)",
    ink: "var(--wf-ink)",
    body: "var(--wf-body)",
    sec: "var(--wf-sec)",
    sub: "var(--wf-sub)",
    border: "var(--wf-border)",
    panel: "var(--wf-panel)",
    white: "var(--wf-surface)",
    success: "var(--wf-success)",
    lime: "var(--wf-lime)",
    error: "var(--wf-error)",
    warn: "var(--wf-warn)",
    blueSoft: "var(--wf-blue-soft)",
    successSoft: "var(--wf-success-soft)",
    errorSoft: "var(--wf-error-soft)"
  };
  const dot = {
    Issuer: "#3c8aff",
    Alice: "#66c800",
    Bob: "#ffd12f",
    Merchant: "#3c8aff"
  };
  const TOKEN = "aUSD";
  const NETWORK = "Base Vibenet";
  const ok = (name, detail) => ({
    kind: "ok",
    name,
    detail: detail || ""
  });
  const err = (name, detail) => ({
    kind: "err",
    name,
    detail: detail || ""
  });
  const nfo = (name, detail) => ({
    kind: "info",
    name,
    detail: detail || ""
  });
  const fmt = n => String(n).replace(/\B(?=(\d{3})+(?!\d))/g, ",");
  const M = v => ({
    v,
    mono: true
  });
  const freshSim = () => ({
    balances: {},
    blocked: null
  });
  const FLOWS = {
    issue: {
      label: "Issue",
      title: "Issue a stablecoin in one call",
      readout: false,
      erc20: "On plain ERC-20 you write, deploy, and audit a token contract.",
      steps: [{
        stage: "Create",
        action: "Create token",
        text: "Create a fiat-backed token. Name, currency, and admin are set at creation.",
        summary: [["Operation", "Create token"], ["Token", TOKEN], ["Standard", "B20"], ["Network", NETWORK]],
        run: () => ({
          entries: [ok("createB20", "stablecoin · aUSD · 0xB20…a1c9"), nfo("initCalls", "grantRole(MINT_ROLE, Issuer)")],
          caption: "One factory call, with no contract to write or audit."
        })
      }, {
        stage: "Confirm",
        action: "Confirm",
        text: "It's live and fully ERC-20 compatible.",
        summary: [["currency()", M('"USD"')], ["decimals()", M("6")], ["Network", NETWORK]],
        run: () => ({
          entries: [nfo("currency()", '"USD"'), nfo("decimals()", "6")],
          caption: "Every wallet and exchange that speaks ERC-20 works with it unchanged."
        })
      }]
    },
    mint: {
      label: "Mint",
      title: "Mint as reserves grow",
      readout: true,
      erc20: "On plain ERC-20, mint permissions and supply caps are custom code.",
      steps: [{
        stage: "Mint",
        action: "Mint 1,000",
        text: "1,000 in fiat lands in reserves. Mint matching supply.",
        summary: [["Operation", "Mint"], ["To", "Alice"], ["Amount", M("1,000 aUSD")], ["Network", NETWORK]],
        run: s => {
          s.balances.Alice = (s.balances.Alice || 0) + 1000;
          return {
            entries: [ok("Transfer", "0x0 → Alice · 1,000")]
          };
        }
      }, {
        stage: "Cap",
        action: "Cap at 1,200",
        text: "Cap supply so circulation can't exceed reserves.",
        summary: [["Operation", "Set supply cap"], ["Cap", M("1,200 aUSD")], ["Network", NETWORK]],
        run: () => ({
          entries: [ok("SupplyCapUpdated", "cap 1,200")]
        })
      }, {
        stage: "Enforce",
        action: "Try minting 500",
        text: "A mint past the cap is rejected by the protocol.",
        summary: [["Operation", "Mint"], ["Amount", M("500 aUSD")], ["Guard", "Supply cap 1,200"], ["Network", NETWORK]],
        run: () => ({
          entries: [err("SupplyCapExceeded", "cap 1,200 · supply 1,000")],
          caption: "Supply can never exceed the cap you set."
        })
      }]
    },
    burn: {
      label: "Burn",
      title: "Burn on redemption",
      readout: true,
      erc20: "On plain ERC-20, redemption bookkeeping is custom code.",
      steps: [{
        stage: "Fund",
        action: "Fund Alice",
        text: "Alice holds 1,000 aUSD.",
        summary: [["Operation", "Mint"], ["To", "Alice"], ["Amount", M("1,000 aUSD")]],
        run: s => {
          s.balances.Alice = 1000;
          return {
            entries: [ok("Transfer", "0x0 → Alice · 1,000")]
          };
        }
      }, {
        stage: "Return",
        action: "Return 400",
        text: "Alice redeems 400 for fiat and returns the tokens.",
        summary: [["Operation", "Transfer"], ["From", "Alice"], ["To", "Issuer"], ["Amount", M("400 aUSD")]],
        run: s => {
          s.balances.Alice -= 400;
          s.balances.Issuer = (s.balances.Issuer || 0) + 400;
          return {
            entries: [ok("Transfer", "Alice → Issuer · 400")]
          };
        }
      }, {
        stage: "Burn",
        action: "Burn 400",
        text: "Retire the returned tokens so supply matches reserves.",
        summary: [["Operation", "Burn"], ["From", "Issuer"], ["Amount", M("400 aUSD")], ["Memo", M('"redeem-8842"')]],
        run: s => {
          s.balances.Issuer -= 400;
          return {
            entries: [ok("Transfer", "Issuer → 0x0 · 400"), ok("Memo", '"redeem-8842"')],
            caption: "The burned tokens leave circulation for good."
          };
        }
      }]
    },
    restrict: {
      label: "Restrict",
      title: "Only approved accounts can hold it",
      readout: true,
      erc20: "On plain ERC-20, KYC gating is a custom transfer hook you build and audit.",
      steps: [{
        stage: "Enable",
        action: "Enable allowlist",
        text: "Turn on your KYC allowlist. Approve Alice and your merchant.",
        summary: [["Operation", "Enable allowlist"], ["Policy", "#2 · ALLOWLIST"], ["Approved", "Alice, Merchant"], ["Network", NETWORK]],
        run: () => ({
          entries: [ok("PolicyCreated", "#2 · ALLOWLIST"), ok("updateAllowlist", "allow Alice, Merchant"), ok("PolicyUpdated", "TRANSFER_SENDER, TRANSFER_RECEIVER → #2")],
          caption: "Every account is denied until you approve it."
        })
      }, {
        stage: "Transact",
        action: "Alice pays merchant",
        text: "Approved accounts transact normally.",
        summary: [["Operation", "Transfer"], ["From", "Alice"], ["To", "Merchant"], ["Amount", M("40 aUSD")]],
        run: s => {
          s.balances.Alice = 100 - 40;
          s.balances.Merchant = 40;
          return {
            entries: [ok("Transfer", "0x0 → Alice · 100"), ok("Transfer", "Alice → Merchant · 40")]
          };
        }
      }, {
        stage: "Enforce",
        action: "Try paying Bob",
        text: "An account you haven't approved is turned away.",
        summary: [["Operation", "Transfer"], ["To", "Bob"], ["Policy", "Allowlist #2"], ["Status", "Denied"]],
        run: () => ({
          entries: [err("PolicyForbids", "TRANSFER_RECEIVER · Bob")],
          caption: "Bob isn't on the allowlist, so the transfer can't land."
        })
      }]
    },
    block: {
      label: "Block",
      title: "Block one address, leave everyone else",
      readout: true,
      erc20: "On plain ERC-20, a blocklist is custom contract code.",
      steps: [{
        stage: "Fund",
        action: "Mint to Bob",
        text: "Bob holds 50 aUSD.",
        summary: [["Operation", "Mint"], ["To", "Bob"], ["Amount", M("50 aUSD")]],
        run: s => {
          s.balances.Bob = 50;
          return {
            entries: [ok("Transfer", "0x0 → Bob · 50")]
          };
        }
      }, {
        stage: "Block",
        action: "Block address",
        text: "A compliance hold comes in for Bob's address.",
        summary: [["Operation", "Block"], ["Account", "Bob"], ["Policy", "Blocklist"], ["Network", NETWORK]],
        run: s => {
          s.blocked = "Bob";
          return {
            entries: [ok("updateBlocklist", "add Bob"), ok("PolicyUpdated", "TRANSFER_SENDER → blocklist")],
            caption: "Only Bob is affected. The token keeps trading for everyone else."
          };
        }
      }, {
        stage: "Enforce",
        action: "Bob tries to pay",
        text: "Bob can no longer move funds.",
        summary: [["Operation", "Transfer"], ["From", "Bob"], ["Policy", "Blocklist"], ["Status", "Denied"]],
        run: () => ({
          entries: [err("PolicyForbids", "TRANSFER_SENDER · Bob")],
          caption: "Blocked by the protocol, not by custom contract code."
        })
      }, {
        stage: "Unblock",
        action: "Unblock",
        text: "When the hold clears, unblock the address.",
        summary: [["Operation", "Unblock"], ["Account", "Bob"], ["Policy", "Blocklist"]],
        run: s => {
          s.blocked = null;
          return {
            entries: [ok("updateBlocklist", "remove Bob")],
            caption: "Bob can transact again."
          };
        }
      }]
    },
    recover: {
      label: "Recover",
      title: "Recover funds from a blocked account",
      readout: true,
      erc20: "On plain ERC-20, there's no safe recovery path without custom code.",
      steps: [{
        stage: "Setup",
        action: "Set up",
        text: "Bob's address is blocked and holds 50 aUSD.",
        summary: [["Operation", "Block + fund"], ["Account", "Bob"], ["Amount", M("50 aUSD")]],
        run: s => {
          s.balances.Bob = 50;
          s.blocked = "Bob";
          return {
            entries: [ok("Transfer", "0x0 → Bob · 50"), ok("updateBlocklist", "add Bob")]
          };
        }
      }, {
        stage: "Reclaim",
        action: "Reclaim funds",
        text: "A holder lost their keys. Reclaim the balance.",
        summary: [["Operation", "Recover"], ["From", "Bob (blocked)"], ["Amount", M("50 aUSD")]],
        run: s => {
          s.balances.Bob = 0;
          return {
            entries: [ok("Transfer", "Bob → 0x0 · 50 (recovered)")],
            caption: "Recovery only works on an account that's already blocked."
          };
        }
      }, {
        stage: "Reissue",
        action: "Reissue",
        text: "Reissue to the holder's new address.",
        summary: [["Operation", "Mint"], ["To", "Alice"], ["Amount", M("50 aUSD")]],
        run: s => {
          s.balances.Alice = (s.balances.Alice || 0) + 50;
          return {
            entries: [ok("Transfer", "0x0 → Alice · 50")],
            caption: "Circulating supply is unchanged: reclaimed, then reissued."
          };
        }
      }]
    },
    pause: {
      label: "Pause",
      title: "Halt activity in an incident",
      readout: true,
      erc20: "On plain ERC-20, a pause switch is custom code, usually all-or-nothing.",
      steps: [{
        stage: "Fund",
        action: "Fund Alice",
        text: "Alice holds 100 aUSD. Everything is running normally.",
        summary: [["Operation", "Mint"], ["To", "Alice"], ["Amount", M("100 aUSD")]],
        run: s => {
          s.balances.Alice = 100;
          return {
            entries: [ok("Transfer", "0x0 → Alice · 100")]
          };
        }
      }, {
        stage: "Pause",
        action: "Pause transfers",
        text: "An incident hits. Halt transfers instantly.",
        summary: [["Operation", "Pause"], ["Scope", "TRANSFER"], ["Network", NETWORK]],
        run: () => ({
          entries: [ok("Paused", "TRANSFER")],
          caption: "Only transfers stop. Pausing is granular."
        })
      }, {
        stage: "Enforce",
        action: "Try a transfer",
        text: "No one can move funds while transfers are paused.",
        summary: [["Operation", "Transfer"], ["Scope", "TRANSFER (paused)"], ["Status", "Blocked"]],
        run: () => ({
          entries: [err("EnforcedPause", "TRANSFER is paused")]
        })
      }, {
        stage: "Resume",
        action: "Resume",
        text: "Resume once the incident is resolved.",
        summary: [["Operation", "Unpause"], ["Scope", "TRANSFER"]],
        run: () => ({
          entries: [ok("Unpaused", "TRANSFER")],
          caption: "Transfers work again."
        })
      }]
    },
    reconcile: {
      label: "Reconcile",
      title: "Match a payment to an order",
      readout: false,
      erc20: "On plain ERC-20, transfers carry no reference, so you run a deposit address per customer.",
      steps: [{
        stage: "Pay",
        action: "Pay with memo",
        text: "Alice pays your processor 25 aUSD, tagged with the invoice.",
        summary: [["Operation", "Transfer"], ["From", "Alice"], ["To", "Merchant"], ["Amount", M("25 aUSD")], ["Memo", M('"invoice-8842"')]],
        run: () => ({
          entries: [ok("Transfer", "Alice → Merchant · 25"), ok("Memo", '"invoice-8842"')],
          caption: "One transaction carries both the payment and the reference."
        })
      }, {
        stage: "Match",
        action: "Match payment",
        text: "The back office matches the payment to the order.",
        summary: [["Operation", "Reconcile"], ["Query", M("(txHash, logIndex−1)")], ["Matched", "invoice-8842 → 25 aUSD"]],
        run: () => ({
          entries: [nfo("query", "Transfer at (txHash, Memo.logIndex − 1)"), nfo("matched", '"invoice-8842" → 25 aUSD ✓')],
          caption: "Reconciliation is one log query, not a deposit address per customer."
        })
      }]
    }
  };
  const order = ["issue", "mint", "burn", "restrict", "block", "recover", "pause", "reconcile"];
  const pinned = flow && FLOWS[flow] ? flow : null;
  const [active, setActive] = useState(pinned || "issue");
  const [sim, setSim] = useState(freshSim);
  const [results, setResults] = useState([]);
  const f = FLOWS[active] || FLOWS.issue;
  const stepIndex = results.length;
  const done = stepIndex >= f.steps.length;
  const cur = done ? f.steps[f.steps.length - 1] : f.steps[stepIndex];
  const select = k => {
    setActive(k);
    setSim(freshSim());
    setResults([]);
  };
  const reset = () => {
    setSim(freshSim());
    setResults([]);
  };
  const runStep = () => {
    if (done) return;
    const s = {
      balances: {
        ...sim.balances
      },
      blocked: sim.blocked
    };
    const out = f.steps[stepIndex].run(s) || ({
      entries: []
    });
    setSim(s);
    setResults(r => [...r, out]);
  };
  const back = () => {
    const n = results.length - 1;
    if (n < 0) return;
    let s = freshSim();
    for (let i = 0; i < n; i++) f.steps[i].run(s);
    setSim(s);
    setResults(r => r.slice(0, -1));
  };
  const pad = n => String(n).padStart(2, "0");
  const ts = n => {
    const t = 42 * 60 + 11 + n;
    return `10:${pad(Math.floor(t / 60) % 60)}:${pad(t % 60)}`;
  };
  const logRows = [];
  let sec = 0;
  results.forEach(res => {
    (res.entries || []).forEach(e => {
      logRows.push({
        t: ts(sec++),
        level: e.kind === "err" ? "ERROR" : e.kind === "info" ? "INFO" : "EVENT",
        name: e.name,
        detail: e.detail,
        kind: e.kind
      });
    });
  });
  f.steps.slice(stepIndex).forEach(st => {
    logRows.push({
      t: ts(sec++),
      level: "PENDING",
      name: st.action,
      detail: "",
      kind: "pending"
    });
  });
  const holders = Object.keys(sim.balances);
  const StatusTag = ({state}) => {
    const map = {
      done: [C.success, "Complete"],
      now: [C.blue, "In progress"],
      future: [C.sub, "Pending"]
    };
    const [col, txt] = map[state];
    return <span className="wf-t-footnote" style={{
      color: col
    }}>{txt}</span>;
  };
  const levelColor = {
    EVENT: C.blue,
    INFO: C.sec,
    ERROR: C.error,
    PENDING: C.sub
  };
  return <div className="wf" style={{
    margin: "22px 0",
    maxWidth: 760,
    borderRadius: 8,
    border: `1px solid ${C.border}`,
    background: C.white,
    overflow: "hidden",
    boxShadow: "var(--wf-shadow)"
  }}>
      <style>{`
        /* ---- Base design system: color tokens (light) ---- */
        .wf {
          --wf-sans: 'Base Sans','Inter Tight',Inter,system-ui,-apple-system,'Segoe UI',Roboto,sans-serif;
          --wf-sans-text: 'Base Sans Text','Inter',system-ui,-apple-system,'Segoe UI',Roboto,sans-serif;
          --wf-mono: 'Base Mono','Roboto Mono',ui-monospace,'SF Mono',Menlo,Consolas,monospace;
          --wf-blue: #0000ff; --wf-on-blue: #ffffff; --wf-cerulean: #3c8aff;
          --wf-ink: #0a0b0d; --wf-body: #32353d; --wf-sec: #5b616e; --wf-sub: #717886; --wf-muted: #787878;
          --wf-border: #dee1e7; --wf-panel: #eef0f3; --wf-surface: #ffffff;
          --wf-success: #66c800; --wf-lime: #b6f569; --wf-error: #fc401f; --wf-warn: #ffd12f;
          --wf-blue-soft: rgba(0,0,255,.06); --wf-success-soft: rgba(102,200,0,.12); --wf-error-soft: rgba(252,64,31,.10);
          --wf-shadow: 0 1px 2px rgba(10,11,13,.04);
        }
        /* ---- Dark theme: system preference ---- */
        @media (prefers-color-scheme: dark) {
          .wf {
            --wf-blue: #4d6bff; --wf-on-blue: #ffffff; --wf-cerulean: #6ea8ff;
            --wf-ink: #ffffff; --wf-body: #dee1e7; --wf-sec: #b1b7c3; --wf-sub: #8a91a0; --wf-muted: #787878;
            --wf-border: #2b2f36; --wf-panel: #17181b; --wf-surface: #0f1012;
            --wf-success: #7cd442; --wf-lime: #b6f569; --wf-error: #ff6a4d; --wf-warn: #ffd12f;
            --wf-blue-soft: rgba(77,107,255,.16); --wf-success-soft: rgba(124,212,66,.16); --wf-error-soft: rgba(255,106,77,.16);
            --wf-shadow: 0 1px 2px rgba(0,0,0,.4);
          }
        }
        /* ---- Dark theme: docs explicit toggle wins over system ---- */
        html.dark .wf, :root[data-theme="dark"] .wf, [data-theme="dark"] .wf {
          --wf-blue: #4d6bff; --wf-on-blue: #ffffff; --wf-cerulean: #6ea8ff;
          --wf-ink: #ffffff; --wf-body: #dee1e7; --wf-sec: #b1b7c3; --wf-sub: #8a91a0; --wf-muted: #787878;
          --wf-border: #2b2f36; --wf-panel: #17181b; --wf-surface: #0f1012;
          --wf-success: #7cd442; --wf-lime: #b6f569; --wf-error: #ff6a4d; --wf-warn: #ffd12f;
          --wf-blue-soft: rgba(77,107,255,.16); --wf-success-soft: rgba(124,212,66,.16); --wf-error-soft: rgba(255,106,77,.16);
          --wf-shadow: 0 1px 2px rgba(0,0,0,.4);
        }
        /* ---- Light theme: docs explicit toggle wins over system dark ---- */
        html.light .wf, :root[data-theme="light"] .wf, [data-theme="light"] .wf {
          --wf-blue: #0000ff; --wf-on-blue: #ffffff; --wf-cerulean: #3c8aff;
          --wf-ink: #0a0b0d; --wf-body: #32353d; --wf-sec: #5b616e; --wf-sub: #717886; --wf-muted: #787878;
          --wf-border: #dee1e7; --wf-panel: #eef0f3; --wf-surface: #ffffff;
          --wf-success: #66c800; --wf-lime: #b6f569; --wf-error: #fc401f; --wf-warn: #ffd12f;
          --wf-blue-soft: rgba(0,0,255,.06); --wf-success-soft: rgba(102,200,0,.12); --wf-error-soft: rgba(252,64,31,.10);
          --wf-shadow: 0 1px 2px rgba(10,11,13,.04);
        }

        .wf, .wf * { box-sizing: border-box; }

        /* ---- Base design system: text variants (mobile → md 768px) ---- */
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        .wf-t-mono { font-family: var(--wf-mono); font-weight: 400; font-size: 11.5px; line-height: 1.5; }
        @media (min-width: 768px) {
          .wf-t-title2 { font-size: 24px; line-height: 32px; }
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          .wf-t-button { font-size: 16px; line-height: 1.4; }
          .wf-t-footnote { font-size: 12px; line-height: 16px; }
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        .wf-nav { display: flex; gap: 20px; }
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        .wf-anim { animation: wf-in .26s ease both; }
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        .wf-pill:hover { color: ${C.ink}; border-color: ${C.sub}; }
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        @media (max-width: 640px) {
          .wf-split { grid-template-columns: 1fr; }
          .wf-rail { border-right: none; border-bottom: 1px solid ${C.border}; }
          .wf-nav { display: none; }
          .wf-stages { overflow-x: auto; }
        }
        @media (prefers-reduced-motion: reduce) { .wf-anim { animation: none !important; } }
      `}</style>

      {}
      {!pinned && <div style={{
    display: "flex",
    alignItems: "center",
    flexWrap: "wrap",
    gap: 6,
    padding: "10px 16px",
    borderBottom: `1px solid ${C.border}`,
    background: C.panel
  }}>
          <span className="wf-t-caption" style={{
    color: C.sub,
    marginRight: 4
  }}>Scenario</span>
          {order.map(k => <button key={k} className={k === active ? "wf-pill wf-pill-on" : "wf-pill"} onClick={() => select(k)}>{FLOWS[k].label}</button>)}
        </div>}

      {}
      <div style={{
    display: "flex",
    alignItems: "center",
    gap: 12,
    padding: "0 16px",
    borderBottom: `1px solid ${C.border}`,
    background: C.white
  }}>
        <div className="wf-stages" style={{
    display: "flex",
    gap: 22,
    flex: 1,
    minWidth: 0,
    overflowX: "auto"
  }}>
          {f.steps.map((st, i) => {
    const state = i < stepIndex ? "done" : i === stepIndex ? "now" : "future";
    const col = state === "future" ? C.sub : state === "now" ? C.blue : C.ink;
    return <span key={i} className="wf-stage" style={{
      color: col,
      borderBottomColor: state === "now" ? C.blue : "transparent",
      fontWeight: state === "now" ? 600 : 500
    }}>
                <span style={{
      fontFamily: "var(--wf-mono)",
      fontSize: 11,
      opacity: .7
    }}>{i + 1}</span>{st.stage}
                {state === "done" && <svg viewBox="0 0 24 24" width="12" height="12" fill="none" stroke={C.success} strokeWidth="3" strokeLinecap="round" strokeLinejoin="round"><path d="M20 6 9 17l-5-5" /></svg>}
              </span>;
  })}
        </div>
        <span className="wf-t-caption" style={{
    color: C.sub,
    border: `1px solid ${C.border}`,
    borderRadius: 5,
    padding: "2px 6px",
    flexShrink: 0
  }}>Demo</span>
        {results.length > 0 && <button onClick={reset} title="Reset" style={{
    display: "inline-flex",
    alignItems: "center",
    justifyContent: "center",
    width: 28,
    height: 24,
    borderRadius: 6,
    background: "transparent",
    border: `1px solid ${C.border}`,
    cursor: "pointer",
    color: C.sec,
    flexShrink: 0
  }}>
            <svg viewBox="0 0 24 24" width="14" height="14" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round"><path d="M21 12a9 9 0 1 1-3-6.7L21 8" /><path d="M21 3v5h-5" /></svg>
          </button>}
      </div>

      {}
      <div className="wf-split">
        {}
        <div className="wf-rail" style={{
    padding: "16px 16px 14px",
    background: C.white
  }}>
          {f.steps.map((st, i) => {
    const state = i < stepIndex ? "done" : i === stepIndex ? "now" : "future";
    const last = i === f.steps.length - 1;
    return <div key={i} style={{
      display: "flex",
      gap: 11
    }}>
                <div style={{
      display: "flex",
      flexDirection: "column",
      alignItems: "center",
      width: 24,
      flexShrink: 0
    }}>
                  <span style={{
      width: 24,
      height: 24,
      borderRadius: "50%",
      display: "inline-flex",
      alignItems: "center",
      justifyContent: "center",
      fontFamily: "var(--wf-sans)",
      fontSize: 11.5,
      fontWeight: 600,
      color: state === "future" ? C.sub : C.onBlue,
      background: state === "done" ? C.success : state === "now" ? C.blue : "transparent",
      border: `1.5px solid ${state === "done" ? C.success : state === "future" ? C.border : C.blue}`
    }}>
                    {state === "done" ? <svg viewBox="0 0 24 24" width="13" height="13" fill="none" stroke={C.onBlue} strokeWidth="3.2" strokeLinecap="round" strokeLinejoin="round"><path d="M20 6 9 17l-5-5" /></svg> : i + 1}
                  </span>
                  {!last && <div style={{
      flex: 1,
      width: 2,
      minHeight: 22,
      marginTop: 4,
      marginBottom: 2,
      background: i < stepIndex ? C.blue : C.border
    }} />}
                </div>
                <div style={{
      flex: 1,
      paddingBottom: last ? 0 : 14,
      minWidth: 0
    }}>
                  <div className="wf-t-body" style={{
      fontWeight: state === "future" ? 400 : 500,
      color: state === "future" ? C.sub : C.ink
    }}>{st.action}</div>
                  <div style={{
      marginTop: 2
    }}><StatusTag state={state} /></div>
                </div>
              </div>;
  })}

          {}
          {f.readout && holders.length > 0 && <div style={{
    marginTop: 14,
    paddingTop: 12,
    borderTop: `1px solid ${C.border}`
  }}>
              <div className="wf-t-caption" style={{
    color: C.sub,
    marginBottom: 8
  }}>Balances</div>
              <div style={{
    display: "grid",
    gap: 6
  }}>
                {holders.map(a => <div key={a} className="wf-t-body" style={{
    display: "flex",
    alignItems: "center",
    gap: 8,
    color: C.body
  }}>
                    <span style={{
    width: 8,
    height: 8,
    borderRadius: "50%",
    background: dot[a] || C.sub,
    flexShrink: 0
  }} />
                    <span style={{
    flex: 1
  }}>{a}</span>
                    {sim.blocked === a && <span className="wf-t-caption" style={{
    color: C.error,
    border: `1px solid ${C.error}`,
    borderRadius: 4,
    padding: "0 4px"
  }}>Blocked</span>}
                    <span style={{
    fontFamily: "var(--wf-mono)",
    fontSize: 12.5,
    fontWeight: 600,
    color: C.ink
  }}>{fmt(sim.balances[a] || 0)}</span>
                  </div>)}
              </div>
            </div>}
        </div>

        {}
        <div style={{
    padding: "16px 18px",
    background: C.white,
    minWidth: 0
  }}>
          {done ? <div className="wf-anim">
              <div className="wf-t-footnote" style={{
    display: "inline-flex",
    alignItems: "center",
    gap: 7,
    fontWeight: 600,
    color: C.success,
    background: C.successSoft,
    borderRadius: 6,
    padding: "5px 10px"
  }}>
                <svg viewBox="0 0 24 24" width="13" height="13" fill="none" stroke={C.success} strokeWidth="3" strokeLinecap="round" strokeLinejoin="round"><path d="M20 6 9 17l-5-5" /></svg>
                Flow complete
              </div>
              <div className="wf-t-body" style={{
    color: C.body,
    margin: "12px 0 16px"
  }}>{f.title} — every step ran onchain in the simulation above.</div>
              <button className="wf-btn2" onClick={reset}>Run again</button>
              <a className="wf-btn" href="/base-chain/network-information/b20-token-standard" style={{
    textDecoration: "none",
    marginTop: 8,
    display: "flex",
    boxSizing: "border-box"
  }}>See technical details →</a>
            </div> : <div className="wf-anim" key={stepIndex}>
              <div className="wf-t-headline" style={{
    color: C.ink
  }}>{cur.action}</div>
              <div className="wf-t-body" style={{
    color: C.sec,
    marginTop: 5
  }}>{cur.text}</div>

              <div style={{
    marginTop: 14,
    border: `1px solid ${C.border}`,
    borderRadius: 8,
    overflow: "hidden"
  }}>
                {cur.summary.map(([k, val], i) => {
    const isM = val && typeof val === "object" && val.mono;
    const v = isM ? val.v : val;
    return <div key={i} style={{
      display: "flex",
      alignItems: "center",
      justifyContent: "space-between",
      gap: 12,
      padding: "9px 12px",
      borderTop: i ? `1px solid ${C.border}` : "none"
    }}>
                      <span className="wf-t-footnote" style={{
      color: C.sec
    }}>{k}</span>
                      <span style={{
      fontFamily: isM ? "var(--wf-mono)" : "var(--wf-sans)",
      fontSize: isM ? 12 : 12.5,
      fontWeight: isM ? 500 : 600,
      color: C.ink,
      textAlign: "right",
      wordBreak: "break-word"
    }}>
                        {k === "Network" && <span style={{
      display: "inline-block",
      width: 7,
      height: 7,
      borderRadius: "50%",
      background: C.cerulean,
      marginRight: 6
    }} />}
                        {v}
                      </span>
                    </div>;
  })}
              </div>

              <div style={{
    marginTop: 14,
    display: "grid",
    gap: 8
  }}>
                <button className="wf-btn" onClick={runStep}>
                  {cur.action}
                  <svg viewBox="0 0 24 24" width="14" height="14" fill="none" stroke="currentColor" strokeWidth="2.4" strokeLinecap="round" strokeLinejoin="round"><path d="M5 12h14M13 6l6 6-6 6" /></svg>
                </button>
                {results.length > 0 && <button className="wf-btn2" onClick={back}>Back</button>}
              </div>
            </div>}
        </div>
      </div>

      {}
      <div style={{
    borderTop: `1px solid ${C.border}`,
    background: C.white
  }}>
        <div style={{
    display: "flex",
    alignItems: "center",
    padding: "10px 16px",
    borderBottom: `1px solid ${C.border}`
  }}>
          <span className="wf-t-headline" style={{
    fontSize: 13,
    color: C.ink
  }}>Transaction event log</span>
        </div>
        <div style={{
    maxHeight: 168,
    overflowY: "auto",
    padding: "6px 0"
  }}>
          {logRows.map((r, i) => <div key={i} className={r.kind === "pending" ? "" : "wf-anim"} style={{
    display: "flex",
    alignItems: "center",
    gap: 10,
    padding: "5px 16px",
    opacity: r.kind === "pending" ? 0.5 : 1
  }}>
              <span style={{
    fontFamily: "var(--wf-mono)",
    fontSize: 11,
    color: C.sub,
    flexShrink: 0
  }}>{r.t}</span>
              <span style={{
    fontFamily: "var(--wf-mono)",
    fontSize: 10.5,
    fontWeight: 600,
    color: levelColor[r.level],
    flexShrink: 0,
    width: 58
  }}>[{r.level}]</span>
              <span style={{
    fontFamily: "var(--wf-mono)",
    fontSize: 11.5,
    color: r.kind === "err" ? C.error : C.body,
    flex: 1,
    minWidth: 0,
    whiteSpace: "nowrap",
    overflow: "hidden",
    textOverflow: "ellipsis"
  }}>
                {r.name}{r.detail ? <span style={{
    color: C.sub
  }}> · {r.detail}</span> : null}
              </span>
              <span style={{
    flexShrink: 0,
    width: 14,
    display: "inline-flex",
    justifyContent: "center"
  }}>
                {r.kind === "err" ? <svg viewBox="0 0 24 24" width="12" height="12" fill="none" stroke={C.error} strokeWidth="3" strokeLinecap="round" strokeLinejoin="round"><path d="M18 6 6 18M6 6l12 12" /></svg> : r.kind === "pending" ? <span style={{
    width: 9,
    height: 9,
    borderRadius: "50%",
    border: `1.5px solid ${C.border}`
  }} /> : <svg viewBox="0 0 24 24" width="12" height="12" fill="none" stroke={C.success} strokeWidth="3" strokeLinecap="round" strokeLinejoin="round"><path d="M20 6 9 17l-5-5" /></svg>}
              </span>
            </div>)}
        </div>
      </div>

      {}
      <div style={{
    padding: "10px 16px",
    background: C.panel,
    borderTop: `1px solid ${C.border}`,
    display: "flex",
    alignItems: "center",
    gap: 10
  }}>
        <span className="wf-t-footnote" style={{
    color: C.sub
  }}>{f.erc20}</span>
      </div>
    </div>;
};

Tie onchain activity back to your books. A **memo** attaches a `bytes32` reference to an operation and emits a `Memo` event alongside it, so reconciliation is a log query instead of a deposit address per customer. Every core call has a memo variant: `mintWithMemo`, `burnWithMemo`, `transferWithMemo`, and `transferFromWithMemo`.

#### Demo

<StablecoinDemo flow="reconcile" />

<Note>
  New to B20? See the [B20 Token Standard](/base-chain/network-information/b20-token-standard) for the concepts and a full launch walkthrough. These samples target `base-std@v1.0.0`, `viem@2.55.11`, and Base Foundry `v1.1.1`.
</Note>

## Attach and read an invoice memo

<CodeGroup>
  ```typescript TypeScript lines wrap expandable highlight={7,10} theme={null}
  import { hexToString, parseEventLogs, parseUnits, stringToHex, type Address } from "viem";
  import { b20Abi } from "../abi.js";
  import { sendContract } from "../write.js";

  export async function payWithMemo(token: Address, merchant: Address) {
    const memo = stringToHex("invoice-8842", { size: 32 });
    const receipt = await sendContract({
      address: token,
      abi: b20Abi,
      functionName: "transferWithMemo",
      args: [merchant, parseUnits("25", 6), memo],
    });
    const [event] = parseEventLogs({ abi: b20Abi, logs: receipt.logs, eventName: "Memo" });
    return hexToString(event.args.memo, { size: 32 }).replace(/\0+$/, "");
  }
  ```

  ```bash CLI lines wrap expandable highlight={2} theme={null}
  MEMO=$(base-cast format-bytes32-string "invoice-8842")
  TX=$(base-cast send "$TOKEN_ADDRESS" "transferWithMemo(address,uint256,bytes32)" \
    "$MERCHANT" 25000000 "$MEMO" --rpc-url "$RPC_URL" --private-key "$PRIVATE_KEY" --json | jq -r .transactionHash)
  base-cast receipt "$TX" --rpc-url "$RPC_URL"
  ```
</CodeGroup>

See the [complete verified B20 examples](https://github.com/base/docs/tree/master/examples/verified-doc-samples) for imports, client construction, and runnable projects.

<Check>
  The receipt contains `Transfer` followed immediately by `Memo`, with `invoice-8842` encoded as `bytes32`.
</Check>

<Note>
  Join a memo to the preceding operation with `(transactionHash, logIndex - 1)`. Keep the offchain invoice ID unique.
</Note>

## See also

* [Accept a B20 payment](/build-on-base/accept-payments/from-humans#accept-b20-with-a-memo) for the app-side flow
* [Query B20 events with the CDP SQL API](https://docs.cdp.coinbase.com/data/sql-api/b20-events) to reconcile at scale