# Changelog

All notable changes to the Frankfurter API will be documented in this file.

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [Unreleased]

### Added

- National Bank of Serbia (NBS) as a data provider. (#301)

### Fixed

- Bank Indonesia rates after its site redesign, and its JPY rates, published per 100 yen.
- Bank of Algeria archive renamed with a prefix.

## [2.6.1] - 2026-10-02

### Changed

- Retired currencies use CLDR names with year ranges instead of '(old)'. (#742)

### Fixed

- Backfill no longer skips a day at each window boundary. (#739)
- National Bank of the Kyrgyz Republic backfills up to today. (#739)
- Retired and non-ISO currency labels in CBU, BOTA, NBP and BOI history. (#740)
- Bank of Israel pre-euro rates published per 10, 100 or 1000 units. (#740)
- Legacy currencies quoted past their redenomination. (#740)
- Banca d'Italia's old afghani quotes, labelled AFN until April 2004. (#741)
- Czech National Bank backfill no longer fails when a window holds whole years. (#743)
- HMRC, IMF, DNB, MAS and CBAR full backfills no longer fail at their coverage start. (#744)
- Successor currencies quoted under retired codes in NBU, BNA, BAM, BDI, CBG, CBU, LB, NBP and BOTA history. (#745)
- National Bank of the Kyrgyz Republic no longer re-dates its frozen BYR rate each week. (#745)
- National Bank of the Republic of North Macedonia's ECU quotes, labelled XBA until May 1999. (#747)
- National Bank of the Republic of Belarus history from July 2016. (#748)
- Bulgarian lev rates from the National Bank of the Republic of Belarus, to December 2025. (#748)
- National Bank of Kazakhstan history from November 1999. (#748)
- Bank of Tanzania history from June 1999. (#748)
- Full backfills keep the first days of CBAR, HNB and BCCH history. (#748)
- Banco Central de Costa Rica history from 1983. (#750)
- One-day provider typos no longer skew blends. (#749)
- Bank of Lithuania's old zloty, ruble, lev, leu and metical quotes, labelled with the new codes. (#751)
- Central Bank of Armenia history for the currencies it no longer quotes. (#751)
- Central Bank of Armenia's pre-2005 tenge and 2000 Tajik ruble rates, published per 10 or 100 units. (#751)
- Finnish markka, Greek drachma, litas, lats and koruna no longer blend past their euro changeover. (#751)
- Old Belarusian ruble quotes labelled BYN in National Bank of Kazakhstan and Central Bank of Armenia history. (#752)
- Central Bank of Armenia's Romanian leu from October 2005 and Turkmen manat from April 2010. (#753)
- Bank of Lithuania history from June 1993. (#754)
- Bank of Lithuania history for the retired currencies it quoted. (#754)
- Bank of Lithuania's 1995 Turkmen manat rows that repeat its Russian ruble rate. (#754)
- Bank of Lithuania's Belarusian ruble rates before the August 1994 denomination. (#754)
- Autoridade Monetária de Macau's interest rate, stored as a currency LIQ to October 2012. (#762)
- Czech National Bank's 1991 Belgian franc and dinar quotes, labelled BEC and YUD. (#762)
- Czech National Bank's clearing ECU (XCU) of 1993 to 1995, missing from the currency catalogue. (#762)
- Natsionalnyi Bank Ukrainy's somoni quotes, labelled ZAL from November 2000 to November 2002. (#762)

Existing installs keep the days the old backfill skipped, since backfill resumes from the newest stored date. Run
`bundle exec rake backfill FULL=1` once after upgrading to fill them; it refetches from each provider's coverage start
and skips rows already stored, so it is safe but slow.

Blends keep their old values for the relabelled history and the screened typos until rebuilt. Run
`bundle exec rake blend:rebuild` once after upgrading; it rebuilds in place, so queries keep reading the tables while it
runs.

## [2.6.0] - 2026-09-30

### Added

- CSV downloads named after the query.
- Query-specific history coverage. (#730)
- Japan Customs (JPC) as a data provider. (#715)
- Banky Foiben'i Madagasikara (BFM) as a data provider. (#400)
- Bank of Mauritius (BOMU) as a data provider. (#370)
- Central Bank of Bosnia and Herzegovina (CBBH) as a data provider. (#376)
- European Commission (INFOREURO) as a data provider. (#713)
- Bank for International Settlements (BIS) as a data provider. (#714)
- COMESA Dollar (CMD) peg. (#706)
- RBA trade-weighted index on provider routes. (#695)
- COMESA Dollar (CMD). (#699)
- HM Revenue & Customs (HMRC) as a data provider. (#172)

### Fixed

- National Bank of Moldova backfills on fresh installs, skipping days without metal prices. (#733)
- Provider-filtered currency lists and coverage dates. (#728)
- Reserve Bank of Malawi Special Drawing Rights quotes as XDR. (#708)
- Bank Negara Malaysia Special Drawing Rights quotes as XDR. (#709)
- Reserve Bank of Australia Special Drawing Rights quotes as XDR. (#704)
- Non-currency series excluded from multi-provider blends. (#698)
- Ecuadorian sucre metadata and retirement cutoff. (#697)
- Bank of Tanzania Special Drawing Rights quotes as XDR. (#696)
- Historical and unknown currency quotes on provider routes. (#667)
- 404 for trailing path segments in V2. (#684)
- Validation of unsupported currency scopes in V2. (#678)
- Strict YYYY-MM-DD date validation in V2. (#677)
- UST leone rates around the 2022 redenomination. (#666)
- Latest rates for providers that publish in arrears. (#685)

### Removed

- Banco Central de Reserva del Perú (BCRP) as a data provider. (#607)

## [2.5.1] - 2026-09-10

### Fixed

- UST entered the blend because `frequency` reset to daily on every start. (#656)

## [2.5.0] - 2026-09-10

### Added

- U.S. Department of the Treasury (UST) as a data provider. (#647)
- `frequency` on `/v2/providers`. (#646)
- Per-provider routes under `/v2/providers/{provider}`. (#643)
- Nicaraguan córdoba (NIO) peg. (#604)

### Changed

- No 5-year cap on single-provider daily ranges. (#644)
- Single-provider rates cross through the provider's own base. (#645)
- Live daily ranges are throttled; excess requests get a 503 with `Retry-After`. (#650)

### Removed

- Banco Central de Nicaragua (BCN) as a data provider. (#604)

### Fixed

- Peg rates no longer override provider rates before the peg took effect. (#603)

## [2.4.0] - 2026-09-09

### Added

- Bank of Zambia (BOZ) as a data provider. (#389)
- Central Bank of Kuwait (CBKKW) as a data provider. (#447)
- Banque du Liban (BdL) as a data provider. (#381)
- Central Bank of Seychelles (CBSSC) as a data provider. (#404)
- Central Bank of Oman (CBO) as a data provider. (#448)
- Banco Central de Venezuela (BCV) as a data provider. (#435)
- Central Bank of the Republic of Azerbaijan (CBAR) as a data provider. (#606)
- Central Bank of Trinidad and Tobago (CBTT) as a data provider. (#378)
- Centrale Bank van Suriname (CBvS) as a data provider. (#426)
- China Foreign Exchange Trade System (CFETS) as a data provider. (#605)
- Palestine Monetary Authority (PMA) as a data provider. (#454)
- Banque Centrale du Congo (BCCCD) as a data provider. (#398)
- Banco de Moçambique (BM) as a data provider. (#386)
- Banco Central de Reserva del Perú (BCRP) as a data provider. (#607)
- Deprecation and Link headers (RFC 9745) on V1 responses pointing to V2.
- Observation dates in V2 `expand=providers` payloads.
- Base currency identity records (`USD/USD = 1`) in V2 rate responses. (#538)

### Changed

- Full-history date ranges on V2 rates are now served in seconds from a precomputed blend, lifting the 5-year cap. (#569, #570)
- V2 latest rates now include provider observations dated one day ahead of the service date for next-day publishers.

### Fixed

- Canonical rate consistency across single-date, latest, and range query shapes. (#570, #573)
- V2 range queries return 503 on timeout instead of computing indefinitely. (#569)
- Relabelled historical predecessor currencies (AZM, TMM, ZMK, RUR, BRR, TJR) previously reported under current codes. (#621, #623, #624)
- Restored stalled provider feeds for BCBO, BCT, BNR, CBE, and SBP. (#547, #548, #564, #576, #580)
- Ingest precision and rounding fixes for CBK, TCMB, and BI feeds. (#579, #584, #585)
- Fixed Docker healthcheck failure under load. (#556)
- Date-relative V2 responses expire from CDN caches at UTC midnight instead of after 24 hours. (#541)

## [2.3.5] - 2026-06-25

### Changed

- Bangko Sentral ng Pilipinas (BSP) now contributes only its official USD/PHP reference rate. (#533)

## [2.3.4] - 2026-06-25

### Fixed

- Single-provider V2 queries now preserve the source's native precision instead of rounding to magnitude bands. (#534)

## [2.3.3] - 2026-06-22

### Fixed

- Restored Reserve Bank of Vanuatu (RBV) rates after bundling missing intermediate TLS certificates.
- Restored Central Bank of Samoa (CBS) rates after handling unescaped spaces in source filenames.
- Labelled pre-1999 Sveriges Riksbank euro rates as ECU (XEU) instead of EUR.
- Prevented ingestion of euro-denominated rates dated before euro inception (1999-01-04).
- Retired legacy currencies (ATS, BEF, DEM, ESP, FRF, ITL, NLG, PTE) at their respective euro changeover dates.
- Weekly and monthly time series no longer omit the current, in-progress period. (#521)

## [2.3.2] - 2026-06-13

### Fixed

- Prevented ingestion of stray future-dated rates that froze incremental provider updates.

## [2.3.1] - 2026-06-11

### Fixed

- Docker containers no longer terminate on startup when the scheduler staggers provider backfills. (#514)

## [2.3.0] - 2026-06-11

### Added

- Banco Central de Bolivia (BCBO) multi-currency basket and commodity reference prices (XAU, XAG, XDR).
- Multi-architecture Docker image builds (`linux/amd64` and `linux/arm64`). (#140)

### Fixed

- Sped up long `/v2/rates` time-series exports with a sliding calculation window.
- Added `stale-while-revalidate` and `stale-if-error` caching directives to time-series exports.
- Fixed 500 errors on date ranges crossing Lithuania's 2015 euro changeover.
- Restored Central Bank of Samoa (CBS) rates following daily filename updates.

## [2.2.0] - 2026-06-01

### Added

- Bangko Sentral ng Pilipinas (BSP) as a data provider.
- Banco Central de Bolivia (BCBO) as a data provider.
- Added `publish_cadence` metadata to `/v2/providers`.

### Fixed

- Set CBC publish cadence to monthly to avoid inaccurate missed publish counts.
- Restored Bank of Tanzania (BOTA) rates after handling CSRF token validation.

## [2.1.1] - 2026-05-29

### Fixed

- Restored alphabetical quote sorting for latest `/v2/rates` responses with carried-forward rates.

## [2.1.0] - 2026-05-24

### Added

- Banco Central de Cuba (BCC) as a data provider.
- Banque Nationale du Rwanda (BNRRW) as a data provider.
- Banco Nacional de Angola (BNA) as a data provider.
- Central Bank of Iraq (CBI) as a data provider.
- Bank of Algeria (BoA) as a data provider.
- Central Bank of Egypt (CBE) as a data provider. (#366)
- Maldives Monetary Authority (MMA) as a data provider.
- Banco Central del Paraguay (BCP) as a data provider.
- State Bank of Pakistan (SBP) as a data provider.
- Central Bank of Sri Lanka (CBSL) as a data provider.
- National Bank of Cambodia (NBC) as a data provider.
- Banque Centrale de Tunisie (BCT) as a data provider.
- National Bank of Tajikistan (NBT) as a data provider.
- National Bank of the Kyrgyz Republic (NBKR) as a data provider.
- Bank of Mongolia (BOM) as a data provider.
- Central Bank of Nigeria (CBN) as a data provider.
- National Bank of Ethiopia (NBE) as a data provider.
- National Reserve Bank of Tonga (NRBT) as a data provider.
- Central Bank of Samoa (CBS) as a data provider.
- Autoridade Monetária de Macau (AMCM) as a data provider.
- Central Bank of Liberia (CBLLR) as a data provider.
- Reserve Bank of Fiji (RBF) as a data provider.
- Da Afghanistan Bank (DAB) as a data provider.
- Central Bank of The Gambia (CBG) as a data provider.
- Reserve Bank of Malawi (RBM) as a data provider.
- Reserve Bank of Vanuatu (RBV) as a data provider.
- Banque de la République du Burundi (BRB) as a data provider.
- Support for Turkmenistani manat (TMT) peg to USD.

### Changed

- Standardized Special Drawing Rights under the ISO 4217 code `XDR`.

### Fixed

- Sorted `/v2/rates` date-range responses chronologically.
- Dropped non-positive rates on ingest to avoid 500 errors.
- Dropped defunct ISO 4217 currency codes past their retirement dates on ingest.

## [2.0.2] - 2026-05-21

### Fixed

- Ensure `/v2/rates` date-range queries return the same rates as `/v2/rates?date=…` for any given date.

## [2.0.1] - 2026-05-19

### Fixed

- Prevented duplicate first row in `/v2/rates` date-range queries.

## [2.0.0] - 2026-05-18

New multi-provider API at `/v2/`. The v1 API is unchanged and remains available indefinitely at `/v1/`.

### Migrating from v1

- Change your base URL from `/v1/latest` to `/v2/rates`.
- Rates are now an array of `{"date", "base", "quote", "rate"}` objects instead of `{"base", "date", "rates": {"USD": 1.23}}`.
- The `symbols` parameter is renamed to `quotes`.
- `from` and `to` are used for date ranges.
- JSONP is not supported in v2.

### Added

- Blended exchange rates from 50+ institutional providers at `/v2/rates`. (#343)
- Single pair endpoints at `/v2/rate/{base}/{quote}` and `/v2/rate/{base}/{quote}/{date}`.
- Provider and currency metadata endpoints at `/v2/providers` and `/v2/currencies`.
- Support for precious metals (XAU, XAG, XPT, XPD) and IMF Special Drawing Rights (XDR). (#333, #335)
- Historical currency coverage for pre-euro and pre-redenomination codes.
- Query-time pegged currency resolution with exact peg anchors. (#323)
- Individual provider breakdowns via `expand=providers`. (#323)
- Provider filtering with `providers` query parameter.
- Time-series downsampling via `group` (`week` or `month`).
- CSV and NDJSON streaming responses.
- Outlier detection and recency-weighted rate blending.
- Stamped observation dates on rates without range carry-forward. (#338)
- Strict query parameter validation (422 on unknown parameters).

## [1.0.0] - 2024-12-04

### Changed

- Added API versioning to URL path (`/v1/`).
- Migrated database storage from PostgreSQL to SQLite.
- Moved domain to <https://api.frankfurter.dev>.

[Unreleased]: https://github.com/lineofflight/frankfurter/compare/v2.6.1...HEAD
[2.6.1]: https://github.com/lineofflight/frankfurter/compare/v2.6.0...v2.6.1
[2.6.0]: https://github.com/lineofflight/frankfurter/compare/v2.5.1...v2.6.0
[2.5.1]: https://github.com/lineofflight/frankfurter/compare/v2.5.0...v2.5.1
[2.5.0]: https://github.com/lineofflight/frankfurter/compare/v2.4.0...v2.5.0
[2.4.0]: https://github.com/lineofflight/frankfurter/compare/v2.3.5...v2.4.0
[2.3.5]: https://github.com/lineofflight/frankfurter/compare/v2.3.4...v2.3.5
[2.3.4]: https://github.com/lineofflight/frankfurter/compare/v2.3.3...v2.3.4
[2.3.3]: https://github.com/lineofflight/frankfurter/compare/v2.3.2...v2.3.3
[2.3.2]: https://github.com/lineofflight/frankfurter/compare/v2.3.1...v2.3.2
[2.3.1]: https://github.com/lineofflight/frankfurter/compare/v2.3.0...v2.3.1
[2.3.0]: https://github.com/lineofflight/frankfurter/compare/v2.2.0...v2.3.0
[2.2.0]: https://github.com/lineofflight/frankfurter/compare/v2.1.1...v2.2.0
[2.1.1]: https://github.com/lineofflight/frankfurter/compare/v2.1.0...v2.1.1
[2.1.0]: https://github.com/lineofflight/frankfurter/compare/v2.0.2...v2.1.0
[2.0.2]: https://github.com/lineofflight/frankfurter/compare/v2.0.1...v2.0.2
[2.0.1]: https://github.com/lineofflight/frankfurter/compare/v2.0.0...v2.0.1
[2.0.0]: https://github.com/lineofflight/frankfurter/compare/v1.0.0...v2.0.0
[1.0.0]: https://github.com/lineofflight/frankfurter/releases/tag/v1.0.0