add initial docs

docs/Makefile

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+# Minimal makefile for Sphinx documentation
+#
+
+# You can set these variables from the command line, and also
+# from the environment for the first two.
+SPHINXOPTS    ?=
+SPHINXBUILD   ?= sphinx-build
+SOURCEDIR     = source
+BUILDDIR      = build
+
+# Put it first so that "make" without argument is like "make help".
+help:
+	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+
+.PHONY: help Makefile
+
+# Catch-all target: route all unknown targets to Sphinx using the new
+# "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
+%: Makefile
+	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)

docs/make.bat

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+@ECHO OFF
+
+pushd %~dp0
+
+REM Command file for Sphinx documentation
+
+if "%SPHINXBUILD%" == "" (
+	set SPHINXBUILD=sphinx-build
+)
+set SOURCEDIR=source
+set BUILDDIR=build
+
+if "%1" == "" goto help
+
+%SPHINXBUILD% >NUL 2>NUL
+if errorlevel 9009 (
+	echo.
+	echo.The 'sphinx-build' command was not found. Make sure you have Sphinx
+	echo.installed, then set the SPHINXBUILD environment variable to point
+	echo.to the full path of the 'sphinx-build' executable. Alternatively you
+	echo.may add the Sphinx directory to PATH.
+	echo.
+	echo.If you don't have Sphinx installed, grab it from
+	echo.http://sphinx-doc.org/
+	exit /b 1
+)
+
+%SPHINXBUILD% -M %1 %SOURCEDIR% %BUILDDIR% %SPHINXOPTS% %O%
+goto end
+
+:help
+%SPHINXBUILD% -M help %SOURCEDIR% %BUILDDIR% %SPHINXOPTS% %O%
+
+:end
+popd

docs/source/conf.py

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+# Configuration file for the Sphinx documentation builder.
+#
+# This file only contains a selection of the most common options. For a full
+# list see the documentation:
+# https://www.sphinx-doc.org/en/master/usage/configuration.html
+
+# -- Path setup --------------------------------------------------------------
+
+# If extensions (or modules to document with autodoc) are in another directory,
+# add these directories to sys.path here. If the directory is relative to the
+# documentation root, use os.path.abspath to make it absolute, like shown here.
+#
+# import os
+# import sys
+# sys.path.insert(0, os.path.abspath('.'))
+
+
+# -- Project information -----------------------------------------------------
+
+project = 'mamba'
+copyright = '2020, QuantStack & mamba contributors'
+author = 'QuantStack & mamba contributors'
+
+# The full version, including alpha/beta/rc tags
+release = '0.5.2'
+
+
+# -- General configuration ---------------------------------------------------
+
+# Add any Sphinx extension module names here, as strings. They can be
+# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
+# ones.
+extensions = [
+	'myst_parser'
+]
+
+# Add any paths that contain templates here, relative to this directory.
+templates_path = ['_templates']
+
+# List of patterns, relative to source directory, that match files and
+# directories to ignore when looking for source files.
+# This pattern also affects html_static_path and html_extra_path.
+exclude_patterns = []
+
+
+# -- Options for HTML output -------------------------------------------------
+
+# The theme to use for HTML and HTML Help pages.  See the documentation for
+# a list of builtin themes.
+#
+html_theme = 'sphinx_book_theme'
+html_logo = "_static/logo.png"
+html_title = "documentation"
+
+
+# Add any paths that contain custom static files (such as style sheets) here,
+# relative to this directory. They are copied after the builtin static files,
+# so a file named "default.css" will overwrite the builtin "default.css".
+html_static_path = ['_static']

docs/source/index.md

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+Welcome to mamba's documentation!
+=================================
+
+Mamba is a fast, robust, and cross-platform package manager that runs on Windows, OS X and Linux (ARM64 and PPC64LE included).
+Mamba is fully compatible with `conda` packages and supports most of conda's commands. In fact, mamba was conceived as a _drop-in_ replacement for conda, offering higher speed and more reliable environment solutions.
+
+Mamba comes with a C++ core (for speed and efficiency), and a clean Python API on top. The core of mamba uses:
+
+- `libsolv` to solve dependencies (the same library used in RedHat dnf and other Linux package managers)
+- `curl` for reliable and fast downloads
+- `libarchive` to extract the packages
+
+To get started with `mamba`, it is currently advised to set up `miniconda` first. You find a installer for miniconda here: https://docs.conda.io/en/latest/miniconda.html
+Once you have miniconda successfully set up, you can use `conda` to install `mamba`. Just type `conda install mamba -n base -c conda-forge` (this will install mamba into your _base_ conda environment -- mamba has to live in the base environment side-by-side with conda).
+
+### Micromamba
+
+```{admonition} Warning
+:class: warning
+
+Note that micromamba is still in early development and not considered ready-for-general-usage yet! It has been used with great succes in CI systems, though, and we encourage this usage.
+```
+
+An alternative to miniconda is micromamba. Micromamba is a statically linked, self-contained executable that comes with all the necessary bits and pieces to initialize and activate conda environments.
+
+
+```{toctree}
+:maxdepth: 2
+:caption: "Contents:"
+
+python_api
+micromamba
+
+```
+
+
+Indices and tables
+==================
+
+* {ref}`Index <genindex>`
+* {ref}`Search <search>`
+
+<!-- * {ref}`modindex <modindex>` -->

docs/source/micromamba.md

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+# micromamba
+

docs/source/python_api.md

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+# The Python API of mamba
+
+The core of mamba is written in C++, but we expose the internals of mamba with a Python API (using pybind11).
+
+You can import the `mamba_api` using `from mamba import mamba_api`.
+
+The mamba_api exposes the following objects:
+
+- `Context`: a singleton configuration object. All global configuration goes through this. From Python you can use the context object like so:
+   ```
+   from mamba import mamba_api
+   mamba_api.Context().conda_prefix = "/home/wolfv/conda"
+   ctx = mamba_api.Context()
+   print(ctx.root_prefix)
+   ```
+
+
+
+Here is an example usage of the mamba_api:
+
+```
+def get_index(
+    channel_urls=(),
+    prepend=True,
+    platform=None,
+    use_local=False,
+    use_cache=False,
+    unknown=None,
+    prefix=None,
+    repodata_fn="repodata.json",
+):
+    real_urls = calculate_channel_urls(channel_urls, prepend, platform, use_local)
+    check_whitelist(real_urls)
+
+    dlist = mamba_api.DownloadTargetList()
+
+    index = []
+    for idx, url in enumerate(real_urls):
+        channel = Channel(url)
+
+        full_url = channel.url(with_credentials=True) + "/" + repodata_fn
+        full_path_cache = os.path.join(
+            create_cache_dir(), cache_fn_url(full_url, repodata_fn)
+        )
+
+        # Channels might not have a name.
+        if channel.name is None:
+            name_and_subdir = channel.subdir
+        else:
+            name_and_subdir = channel.name + "/" + channel.subdir
+        sd = mamba_api.SubdirData(name_and_subdir, full_url, full_path_cache)
+
+        sd.load()
+        index.append((sd, channel))
+        dlist.add(sd)
+
+    is_downloaded = dlist.download(True)
+
+    if not is_downloaded:
+        raise RuntimeError("Error downloading repodata.")
+
+    return index
+
+class MambaSolver:
+    def __init__(self, prefix, channels, platform):
+
+        api_ctx = mamba_api.Context()
+        api_ctx.conda_prefix = prefix
+
+        self.channels = channels
+        self.platform = platform
+        self.index = get_index(channels, platform=platform)
+        self.local_index = []
+        self.pool = mamba_api.Pool()
+        self.repos = []
+
+        start_prio = len(channels)
+        priority = start_prio
+        subpriority = 0  # wrong! :)
+        for subdir, channel in self.index:
+            repo = mamba_api.Repo(
+                self.pool,
+                str(channel),
+                subdir.cache_path(),
+                channel.url(with_credentials=True),
+            )
+            repo.set_priority(start_prio, subpriority)
+            start_prio -= 1
+            self.repos.append(repo)
+
+        self.local_repos = {}
+
+    def solve(self, specs, prefix):
+        """Solve given a set of specs.
+        Parameters
+        ----------
+        specs : list of str
+            A list of package specs. You can use `conda.models.match_spec.MatchSpec`
+            to get them to the right form by calling
+            `MatchSpec(mypec).conda_build_form()`
+        Returns
+        -------
+        solvable : bool
+            True if the set of specs has a solution, False otherwise.
+        """
+        solver_options = [(mamba_api.SOLVER_FLAG_ALLOW_DOWNGRADE, 1)]
+        api_solver = mamba_api.Solver(self.pool, solver_options)
+        _specs = specs
+
+        api_solver.add_jobs(_specs, mamba_api.SOLVER_INSTALL)
+        success = api_solver.solve()
+
+        if not success:
+            error_string = "Mamba failed to solve:\n"
+            for s in _specs:
+                error_string += f" - {s}\n"
+            error_string += "\nwith channels:\n"
+            for c in self.channels:
+                error_string += f" - {c}\n"
+            pstring = api_solver.problems_to_str()
+            pstring = "\n".join(["   " + l for l in pstring.split("\n")])
+            error_string += f"\nThe reported errors are:\n⇟{pstring}"
+            print(error_string)
+            exit(1)
+
+        package_cache = mamba_api.MultiPackageCache(pkgs_dirs)
+
+        t = mamba_api.Transaction(api_solver, package_cache)
+        return t
+```
+
+Let's walk through this example:
+
+We first use the `get_index` method to download repository data from the channels.