Pros of Substrate

• More active development with frequent updates and contributions
• Extensive documentation and tutorials for developers
• Flexible and modular architecture allowing for customizable blockchain creation

Cons of Substrate

• Steeper learning curve due to complex architecture
• Larger codebase, potentially requiring more resources to maintain
• Rust-based, which may be less familiar to some developers compared to Erlang

Code Comparison

Substrate (Rust):

#[pallet::weight(10_000 + T::DbWeight::get().writes(1))]
pub fn do_something(origin: OriginFor<T>, something: u32) -> DispatchResult {
    let who = ensure_signed(origin)?;
    <Something<T>>::put(something);
    Self::deposit_event(Event::SomethingStored(something, who));
    Ok(())
}

Aeternity (Erlang):

-spec spend(aec_keys:pubkey(), non_neg_integer(), non_neg_integer(), aetx:tx_ttl(), aec_keys:pubkey()) ->
                   {ok, aetx:signed_tx()} | {error, term()}.
spend(RecipientPubkey, Amount, Fee, TTL, SenderPubkey) ->
    {ok, Tx} = aec_spend_tx:new(#{sender_id => aeser_id:create(account, SenderPubkey),
                                  recipient_id => aeser_id:create(account, RecipientPubkey),
                                  amount => Amount,
                                  fee => Fee,
                                  ttl => TTL,
                                  nonce => aec_accounts:next_nonce(SenderPubkey)}),
    {ok, aec_keys:sign(Tx)}.

Pros of Cosmos SDK

• More extensive documentation and developer resources
• Larger and more active community, with broader ecosystem support
• Modular architecture allowing for easier customization and extension

Cons of Cosmos SDK

• Steeper learning curve due to its complexity and extensive features
• Potentially higher resource requirements for running nodes

Code Comparison

Cosmos SDK (Go):

func (app *SimApp) BeginBlocker(ctx sdk.Context, req abci.RequestBeginBlock) abci.ResponseBeginBlock {
    return app.mm.BeginBlock(ctx, req)
}

Aeternity (Erlang):

-spec begin_block_tx(aec_blocks:block()) -> ok.
begin_block_tx(Block) ->
    aec_tx_pool:new_block(Block).

The Cosmos SDK code snippet shows a more modular approach, utilizing the module manager (app.mm) to handle the begin block logic. Aeternity's code appears more straightforward but less flexible.

Cosmos SDK offers a more comprehensive framework for building blockchain applications, with a focus on interoperability and customization. Aeternity provides a simpler, more focused platform for smart contracts and decentralized applications.

Both projects have their strengths, with Cosmos SDK being more suitable for complex, interconnected blockchain ecosystems, while Aeternity may be preferable for simpler, more specific use cases.

Pros of go-ethereum

• Larger and more established community, with extensive documentation and resources
• More mature codebase with longer history of development and refinement
• Wider adoption and ecosystem support, including numerous tools and dApps

Cons of go-ethereum

• Higher complexity and steeper learning curve for developers
• Slower transaction processing and higher gas fees during network congestion
• Less flexible consensus mechanism compared to Aeternity's hybrid approach

Code Comparison

go-ethereum (Geth):

func (s *Ethereum) Start() error {
    if err := s.startEthService(); err != nil {
        return err
    }
    return nil
}

Aeternity:

start(Config) ->
    case aec_chain_state:start_link() of
        {ok, ChainPid} ->
            {ok, #state{config = Config, chain_pid = ChainPid}};
        {error, Reason} ->
            {error, Reason}
    end.

The code snippets show different approaches to starting the respective blockchain services. go-ethereum uses a more imperative style with error handling, while Aeternity employs pattern matching and a functional approach typical of Erlang.

Pros of Fabric

• Broader enterprise adoption and larger community support
• More flexible permissioning and privacy controls
• Modular architecture allowing for customizable consensus mechanisms

Cons of Fabric

• Higher complexity and steeper learning curve
• Potentially slower transaction processing due to multiple layers
• Less focus on native cryptocurrency functionality

Code Comparison

Fabric (Go):

func (s *SmartContract) CreateAsset(ctx contractapi.TransactionContextInterface, id string, color string, size int, owner string, value int) error {
    asset := Asset{
        ID:    id,
        Color: color,
        Size:  size,
        Owner: owner,
        Value: value,
    }
    assetJSON, err := json.Marshal(asset)
    if err != nil {
        return err
    }
    return ctx.GetStub().PutState(id, assetJSON)
}

Aeternity (Sophia):

contract AssetRegistry =
  record asset = {
    id : string,
    color : string,
    size : int,
    owner : address,
    value : int }

  stateful entrypoint create_asset(id' : string, color' : string, size' : int, owner' : address, value' : int) =
    let asset = { id = id', color = color', size = size', owner = owner', value = value' }
    put(state{assets[id'] = asset})

Both examples showcase asset creation, but Fabric uses Go with a more verbose JSON approach, while Aeternity uses Sophia with a more concise record-based structure.

Pros of go-algorand

• Written in Go, which offers better performance and concurrency handling compared to Erlang
• More active development with frequent commits and releases
• Larger community and ecosystem support

Cons of go-algorand

• More complex codebase with a steeper learning curve
• Higher resource requirements for running a node
• Less focus on scalability compared to Aeternity's state channels approach

Code Comparison

go-algorand

func (node *AlgorandFullNode) Start() {
    node.net.Start()
    node.ledger.Start()
    node.agreement.Start()
    node.txHandler.Start()
}

aeternity

start() ->
    aec_db:load_database(),
    aec_chain_state:start_link(),
    aec_peers:start_link(),
    aec_tx_pool:start_link(),
    aec_conductor:start_link().

Both projects implement similar node startup processes, initializing core components like networking, ledger/chain state, and transaction handling. However, go-algorand's implementation in Go offers a more concise and readable syntax, while aeternity's Erlang code leverages the language's built-in concurrency features with the start_link() calls.