Comparisons · PG-14 · Blnk # Ledgerbook AI vs Blnk Both are headless, both are developer-first, both are self-hostable — at different layers, with different immutability stances. Facts captured 2026-09-19, sourced below. Last verified 2026-09-19 · re-verified quarterly · corrections → [contact](/contact) Blnk is an open-source fintech ledger: an Apache-2.0 core for wallet, payment and lending products, with inflight transactions, a reconciliation engine and 1,100-plus tests in the repository (their GitHub, fetched 2026-09-19). Ledgerbook is an accounting data layer: chain-hashing enabled by default, immutable balances, typed corrections, and a governed agent write surface that works self-hosted and air-gapped. The difference is the layer. Blnk moves money on a balance ledger; Ledgerbook keeps the books those movements reconcile into — multi-dimensional accounts, multi-entity consolidation and OCEL 2.1 provenance. If your build is fintech primitives under one permissive licence, Blnk is a fair default; below we concede that plainly and compare on facts. Verified 2026-09-19 · sources: blnkfinance.com pricing and product pages · docs.blnkfinance.com (MCP, changelog, config) · GitHub repository (dossiers 11/11b, same date) ## Side by side | Dimension | Blnk | Ledgerbook AI | |---|---|---| | Deployment | Apache-2.0 core deployable (`docker compose up`, bring-your-own Postgres); managed Cloud tiers and on-prem/BYOC options. their install docs, 2026-09-19 | Self-host and air-gap first-class: single node, basic HA, offline bundle with zero egress. NFR-6 · PH-1 Embedded class and multi-region residency are ◇ Roadmap | | Immutability & corrections | A database trigger blocks updates (metadata excepted); a SHA-256 chain exists and ships disabled until an operator enables it in config; balances mutate in place, with history reconstructed from transactions and snapshots. their config docs + repo review, 2026-09-19 | Chain hash on every Final entry, enabled by default and not disableable by writers; balances are derived, never mutated; corrections only as typed reversing, adjusting or restating entries. FR-118/119/123–125/205/214 · PH-1 | | Agent write path (MCP) | MCP is Cloud-only: 'All MCP traffic is routed through Blnk Cloud. AI clients never connect directly to your Core instance.' Self-hosted deployments get no agent surface. their MCP reference, 2026-09-19 | MCP read/propose inside the deployment, with the same semantics and error taxonomy as HTTP — air-gapped, with your local model. Agents cannot approve, finalize or correct, enforced at the credential. T2/T3 tiers are ◇ Roadmap. FR-220/343 · PH-1 | | Accounting depth | Fintech ledger primitives: inflight transactions, refunds, scheduled entries, multi-currency balances, a reconciliation engine. FX conversion was removed from the codebase; no accounting dimensions, multi-entity consolidation or statutory semantics. their docs + repo, 2026-09-19 | Multi-dimensional accounts and dimension registry; per-scenario double-entry; multi-entity intercompany as explicit paired entries; posted FX conversion with the rate locked at posting. FR-102/103/128–134/335 · PH-1 Compliance packs are ◇ Roadmap. | | Provenance / audit export | Journal plus balance snapshots; an opt-in chain verification CLI; per-status webhooks from one global URL. No OCEL export published. their changelog and docs, 2026-09-19 | OCEL 2.1 JSON export plus an independently runnable verifier; a provenance event on every mutation with who/when/where. Bundled export formats and packaged evidence sets are ◇ Roadmap. FR-905/121 · PH-1 | | Commercial shape | Apache-2.0 core free; published tiers — sandbox, production and enterprise — plus support plans; ISO 27001 and GDPR posture. their pricing page, 2026-09-19 | Open-core, source-available stance (licence text to publish before commercial launch); quote-led enterprise, no per-transaction metering on the base. OI-12/19 | Sources: [blnkfinance.com/pricing](https://blnkfinance.com/pricing) · [docs.blnkfinance.com/cloud/reference/mcp](https://docs.blnkfinance.com/cloud/reference/mcp) · [docs.blnkfinance.com/changelog](https://docs.blnkfinance.com/changelog) (hash chain opt-in, verify CLI) · [github.com/blnkfinance/blnk](https://github.com/blnkfinance/blnk) (licence, tests) — all fetched 2026-09-19. No funding figure is printed for Blnk: public databases conflate Blnk Finance with a same-named company in a different sector, so a number here would be unreliable. For our column: product specification, PH-1 and Roadmap as tagged. ## Where Blnk wins — and when to choose it Concessions first, without caveats. - **The cleanest licence in the segment.** Apache-2.0 across the repository with no enterprise carve-out — everything in the core is yours to self-host and modify, and an independent licence survey names that as the cohort's cleanest split (2026-09-11). - **Transparent, published pricing.** Sandbox and production tiers and separate support plans are public, not quote-only — buyers can budget from the page. - **A genuinely complete OSS core.** Inflight transactions, a reconciliation engine with matching strategies and rule-based monitoring live in the free core, with 1,100-plus tests including invariant fuzzing in the repository (their GitHub, 2026-09-19). - **Operational breadth in Cloud.** Back-office UI, data-lake queries over ledger history and agent-job APIs come managed, which is real leverage for small teams. ## How Ledgerbook differs — three things, no more ### Chain on by default Every Final entry is chain-hashed by default and the chain cannot be switched off by writers or configuration — a deliberate difference from ledgers where hashing waits for an operator to enable it. Verification runs online or offline, and a signed export replays into a fresh deployment. FR-118/119/121/813 · PH-1 ### Self-hosted agent surface The MCP read/propose surface ships inside the deployment, air-gap included, so self-hosting does not cost you agent access. Governance sits at the credential: proposal scopes for agents, approvals and posting reserved to humans and policy. FR-343/220 · PH-1 read/propose; full tool surface Roadmap ### An accounting layer, not a balance layer Ledgerbook keeps statutory-grade books: multi-dimensional accounts, multi-entity consolidation, a Provisional → Final lifecycle with typed corrections, and provenance exports an auditor can load without our help. FR-102/103/128/200–211/905 · PH-1 ## Ask any ledger vendor these seven questions The checklist behind this page — run it against us, and against anyone else on your shortlist. - What is the immutability proof object — can a third party verify it without ledger access? ours: [online and offline chain verification](/immutable-ledger#verify) · PH-1 - What gate sits in front of agent writes, and can an agent credential approve or post? ours: [proposal-only credentials](/mcp-server#governance) · PH-1 - Where can the data legally run — self-host, BYOC, air-gap — and does the agent surface survive that deployment? ours: [self-host and air-gap first-class](/self-host) · PH-1 - What export can an auditor take away, and can they load it independently? ours: [OCEL 2.1 JSON + verifier](/provenance-ocel2) · PH-1 - What happens after a Final entry turns out wrong — edit, delete, or typed correction? ours: [typed corrections only — reversal, adjustment or restatement](/provisional-lifecycle#corrections) · PH-1 - How granular is access control — token, scope, row — and does it hold on exports too? ours: [row-level, identical on every surface](/mcp-server#governance) · PH-1 - What is shipped today versus Roadmap, and is every unshipped item labelled as such? ours: [dated changelog](/changelog) · phase labels site-wide ## Blnk comparison FAQ Choose on the layer you need. Blnk is a strong fit when you are building wallets, payment flows or lending primitives and want a permissively licensed core you operate yourself. Ledgerbook fits when the requirement is accounting truth: a statutory-grade book of record under your estate, with consolidation, typed corrections and audit exports. They can also coexist — Blnk as a money-movement system of entry, Ledgerbook as the ledger of record above it. It is a design choice, stated by them: their SHA-256 chain exists and ships disabled until an operator enables it (their configuration docs, 2026-09-19). Ledgerbook makes the opposite choice — chain-hashing is on for every ledger by default and cannot be disabled by writers — because in accounting, tamper-evidence that can be switched off is a configuration question an auditor has to ask. We state the difference; we do not call theirs wrong. In Blnk, MCP traffic routes through Blnk Cloud by design — quote their docs: 'All MCP traffic is routed through Blnk Cloud. AI clients never connect directly to your Core instance.' A strictly self-hosted or air-gapped deployment therefore has no agent surface. In Ledgerbook, the MCP read/propose surface is part of the deployment: it runs air-gapped against your own local model, with no cloud hop. Not the same licence. Blnk's core is Apache-2.0 with no enterprise carve-out — genuinely permissive, and we name that as a strength. Ledgerbook is open-core: the core engine is source-available under a recorded stance, with exact licence text published before commercial launch and pack or module licensing still to be confirmed. If an OSI-approved licence is a hard requirement today, that is a real difference to weigh. ## Pick the layer, then the product Design partners get the side-by-side pack, including the axes where the free option is the better answer. Blnk is the trademark of its owner and is used here as an adjective for comparison only; no logos, no implied endorsement or partnership. Every competitor claim above traces to a public source fetched on 2026-09-19 (dossiers 11 and 11b, same date; the chain defaults and balance behaviour include a review of the public repository) and is re-verified quarterly. If a fact is wrong or stale, tell us and it is corrected and re-dated.